Grow a marvelous crystal garden with these fast-growing crystals. The centers of four flower cards bloom into delicate crystal structures in just a few hours. You can practically see the crystals form before your eyes on the branches of filter-paper trees. Learn about how and why crystals form, and experiment with different colored flowers.
• This kit provides the tools and instructions to learn how electronics work.
• The innovative snap-together blocks make learning electronics fun and accessible.
• The components in the kit include capacitors, resistors, transistors, and more
• 64-page, full-color manual guides you through 70 circuit building experiments
Fun Circuit Building Experiments for Beginners Construct circuits with colorful electric building blocks to learn about electricity and how electronic devices work. With the innovative snap-together blocks in this kit, children eight and up can safely and easily begin experimenting with electronic circuits. These building blocks are specially designed to make learning electronics fun and accessible. Because the blocks are brightly colored and have unique shapes, it is easy to follow the assembly diagrams to construct functional circuits. And because the circuit symbols are printed directly onto the blocks, you can quickly become familiar with the symbols and learn how to read circuit diagrams. The fun building projects include an alternating blinker, a police siren, an ambulance siren, an alarm system, a light detector, a conductivity tester, a rain warning system, a timer, and logic circuits. The electronic components in this kit include capacitors, resistors, transistors, LEDs (light emitting diodes), a phototransistor, a switch, 30 contact blocks, cable blocks, a battery holder, a speaker, and a sound integrated circuit. The 64-page, full-color experiment manual guides you through 70 circuit building experiments with easy-to-follow diagrams. This kit provides kids with the tools and instructions they need to experiment with their own hands and learn firsthand how electronics work.
Hydropower has been used for hundreds of years in watermills and is now commonly used to generate electricity in applications such as hydroelectric dams and tidal power plants. Explore the power of water by building models and conducting experiments with them. Learn about how different devices are used to extract useful energy from moving water — from a waterwheel in a small stream to a giant turbine in a tidal power station.
Build a waterwheel, a sawmill, and a hammer mill to harness the energy of moving water to do different types of physical work. Investigate the intriguing properties of water by performing experiments involving surface tension, adhesion, and cohesion. Learn about water pressure by building a water tower, communicating vessels, and a water fountain.
Construct a hydroelectric power station to generate electricity and light an LED. Learn about where the energy in ocean waves, tides, and rivers comes from, and discover how we can generate electricity from them. The full-color, 32-page experiment manual offers illustrated instructions and scientific information.
12 Experiments and building projects
Harness mechanical energy from water to do physical work
Generate electricity to light an LED Learn the physics of water turbines
Discover why hydropower is a promising source of energy.
Ages: 8+
Experiments: 12
Piece Count: 105
Manual Pages: 32
Product Dimensions: 14.6 x 11.5 x 2.3 in.
Product Weight: 2.1 lbs
Manual Dimensions: 5.5 x 8.25 in.
Batteries Required: N/A
Country of Origin: Taiwan
Year Released: 2009
Discover the science of living things with this complete introductory microscope kit. The beautifully illustrated experiment manual guides you through observations of many living specimens found in and around your home: onion cells, pond water, chloroplasts, plant stem cross sections, microorganisms, mouth cells, meat cells, different types of hair and fur, dust mites, bugs, pollen in honey, and much more.
See how an onion cell shrivels and how an paramecium wiggles. Analyze the differences between the hair on your head and the sheep’s hair in your wool sweater. The kit includes slides, cover slips, and many helpful tools. Learn how to use these tools to prepare slides and how to use the microscope to examine them.
Investigate how the lenses in a microscope bend light to magnify images. When the ocular lens, or eyepiece lens, works together with the three objective lenses, the result is a total magnification power of 60x, 150x, or 600x. The microscope has a battery-powered light to light up the specimens. The full-color, 32-page manual covers microscope setup, usage, and many fascinating observations of biological specimens.
Discover the science of living things with this complete introductory microscope kit. The beautifully illustrated experiment manual guides you through observations of many living specimens found in and around your home: onion cells, pond water, chloroplasts, plant stem cross sections, microorganisms, mouth cells, meat cells, different types of hair and fur, dust mites, bugs, pollen in honey, and much more.
See how an onion cell shrivels and how an paramecium wiggles. Analyze the differences between the hair on your head and the sheep’s hair in your wool sweater.
The kit includes slides, cover slips, and many helpful tools. Learn how to use these tools to prepare slides and how to use the microscope to examine them. Investigate how the lenses in a microscope bend light to magnify images.
When the ocular lens, or eyepiece lens, works together with the three objective lenses, the result is a total magnification power of 60x, 150x, or 600x. The microscope has a battery-powered light to light up the specimens. The full-color, 32-page manual covers microscope setup, usage, and many fascinating observations of biological specimens.
Ages: 8+
Experiments: 11
Piece Count: 13
Manual Pages: 32
Product Dimensions: 8.5 x 12.5 x 4.9 in.
Product Weight: 1.5 lbs
Manual Dimensions: 5.5 x 8.25 in.
Batteries Required: 2 AA
Country of Origin: China
Year Released: 2020
• Introductory chemistry set designed specifically for young kids
• Conduct experiments to identify different chemicals
• Discover the invisible gas carbon dioxide and its very visible effects
• 48-page manual guides young chemists through 25 experiments
Kick off a chain reaction of fun-filled experiments with this introductory chemistry set designed specifically for young kids. Junior chemists can safely explore simple chemistry using the tools in this kit and common household substances from the kitchen, bathroom, and laundry room. Learn how to use basic chemistry equipment such as filters, test tubes, pipettes, and measuring spoons, and beakers. Make your own test tube racks out of plaster and learn about the chemical reaction that formed them. Conduct experiments to identify different chemicals using reactions, heat, evaporation, and crystallization. Examine the composition of inks and dyes with chromatography experiments, where colors magically separate from one another on a filter paper disk. Explore the properties of water, soaps, and oils. Experiment with acids and bases using indicators (pH strips and cabbage juice) to identify them. Make fizzy reactions with acids and bases to dissolve shells and inflate balloons. Discover the invisible gas carbon dioxide and its very visible effects. The full-color, 48-page manual guides inquisitive young chemists and their adult supervisors through safely conducting each of the 25 experiments.
• Discover the invisible world of magnetic forces
• "Draw" pictures with magnets
• Test the strength of magnets
Discover the invisible world of magnetic forces. Draw pictures with magnets. Make a magnetic driving test. Test the strength of magnets and learn how to lift objects without touching them! Explore the basic principles of magnetism with twelve hands-on experiments. Includes a full-color 16-page guidebook with simple step-by-step instructions and lots of pictures. Kit contains the necessary parts. Ages 5 and up.
It’s time to start mixing things up! In this pretend STEM scenario, you are a chemist for a bath and body products company and it’s your job to make and test different cosmetic products. Use the tools in your laboratory to employ different scientific techniques and essential chemistry principles to make soaps and bath bombs. Try out different additives to affect the color, smell, and other qualities of the products you make.
Real science and pretend play come together in this activity-filled kit that can be used alone or as an extension of the Ooze Labs Chemistry Station (a Parents’ Choice Silver Honor winner!). As you mold different glycerin soap shapes, you learn about the chemical properties of soap that help it pick up and wash away dirt. While you’re concocting bath bombs, you learn about how acids and bases combine to form fizzing reactions, and what a pH level is. Expand your cosmetics knowledge with an overview of the biology of skin care and other science related to soap and bath products. All materials and chemicals are non-toxic.
Ages: 6+
Experiments: 10
Piece Count: 35
Manual Pages: 24
• Build spectacular models and devices, such as a wind tunnel and a hydraulic lift
• Study advanced topics like fluid dynamics, energy, hydraulics, and pneumatics
• Investigate how air & water rest and flow, what they can carry and how they move
• More than 212 parts are included in this kit
• Learn why a streamlined shape lets a car drive faster
• Learn how power plants convert a current of water into electrical current
Physics Pro is our biggest, most advanced physics kit. With this kit, you can continue your study of statics and dynamics from previous lessons and begin your study of more advanced topics in physics, including fluid dynamics, energy, oscillation, hydraulics, and pneumatics. By adding advanced topics like fluid dynamics to your physics repertoire, you can now build some really spectacular models and devices, such as a wind tunnel, pneumatic shocks, and a hydraulic lift. You will see how physics extends far beyond the classroom, giving us an amazing set of tools that can be applied in the real world to engineer marvelous things. The main focus of the kit is the behavior of the two most important fluids in our world — water and air — and objects immersed in them. You will investigate how air and water rest and flow, what they can carry and how they move. With experiments and models, you will find out what forces work on them and what kinds of energy they possess. You will learn how ships float and airplanes fly, why a streamlined shape lets a car drive faster and how power plants convert a current of water into electrical current. The 96-page, full-color experiment manual has two major sections. In the first part, you will enter the physics lab, where you will get to know the properties of air and water and become familiar with currents and energy. There is a series of 17 experiments in which you will start building smaller models. In the second part, you will move on to the workshop, where you will build 14 larger models of complex real-world devices. More than 212 parts are included in this kit, which are compatible with our other Physics kits.
• Almost every form of energy we use originates as energy from the sun
• Explore the topic of solar energy, focusing on photovoltaic cells
• Learn how solar cells transform light into electrical energy
• Learn how motors and mechanical devices can optimize the work done by energy
• Build a praying mantis model that moves like an insect and is solar powered
In one way or another, almost every form of energy we use originates as energy from the sun. Solar energy directly powers photovoltaic cells and thermal collectors. Indirectly, we get power from plants grown by the sun, oceans heated by the sun, and Earth's weather systems sustained by the sun. Even the energy stored in fossil fuels originated as energy from the sun, captured by plants and animals millions of years ago. Physics Solar Workshop explores the topic of solar energy, focusing on photovoltaic cells. By building 12 models and conducting 30 experiments, you will learn how solar cells transform light into electrical energy, and how motors and mechanical devices can optimize the work done by this energy. You will build different types of vehicles and machines to demonstrate how gears can convert and transform power for different needs. There are 320 parts, which are also compatible with the other kits in our Physics line. The 64-page book offers illustrated instructions for the projects. Developed with Greenpeace in Germany. Ages 8 and up.
• Kit includes more than 300 building pieces
• Build a windmill, two-speed crane, force scale, sail car, mars robot, and more
• Experiment with gears, levers, screws, inclined planes, pulleys, wheels and axles
• Learn and understand the most fundamental physics equations
• It is a 64-page, full-color experiment manual
• Centrifuge, pinball, centrifugal switch, ship's lantern, and dozens of other models
• Ages 8 and up
Force = mass x acceleration and don't forget to factor in the fun. This kit studies the Science of Matter and Energy. Through building 36 models and conducting subsequent experiments with the models, you will learn the fundamental laws of mechanical physics. This hands-on approach is both fun and effective because the principles of physics are demonstrated right in front of you. Physics Workshop includes more than 300 building pieces. The full-color 64-page manual presents assembly instructions, experiments and explanations in a richly-illustrated, easy-to-follow manner. 73 Experiments and Activities: Build a windmill, crane, sail car, mars robot, hammer machine, centrifuge, scale and dozens of other models. Experiment with simple machines: gears, levers, screws, inclined planes, pulleys, wheels and axles. Learn and understand the most fundamental physics equations. Read about amazing real-world applications for physics.
• Build your own motorized vehicles and machines with a wireless remote control unit
• Unique six button infrared remote control
• Three motors can be combined to make complex vehicles and machines
• Assemble up to 10 models
• 48-page illustrated color instruction book included
• Kit comes with everything you need
• Ages 8 and up
The unique six button infrared remote allows you to control three different motors simultaneously, moving each of them forward or in reverse, with easy-to-activate touch sensors. The three motors can be combined to make complex vehicles and machines in numerous configurations limited only by your imagination. Assemble ten models demonstrating different ways in which the motors can be used including a bulldozer, car, three-wheeler, crane, antique car, plow, folding car, formula one racer, three-blade dozer, and robotic arm. After you have built the models in the instructions, you can design your own remote control creations! The kit comes with three motors, remote control unit, battery holder, and building blocks. Collaborate with your fellow junior engineers to build fantastic and functional remote-control creations! The 48-page color instruction book gives illustrated step-by-step instructions for the models to help children learn through play and develop their mechanical understanding, creative thinking skills, and hand-eye coordination.
• Build your own simple solar thermal updraft towers
• Collect the sun’s energy and use it to spin five colorful turbines
• Learn about thermal updrafts and solar thermal energy.
Solar thermal energy refers to the technology of collecting solar energy in the form of heat and making it useful, for example, by converting it into electricity or heating homes. Huge solar thermal towers are being installed in sunny places around the world to convert the sun's heat into electricity via turbines powered by hot air. With this kit, you can build your own simple solar thermal updraft towers to collect the sun's energy and use it to spin colorful turbines. Test the solar turbines in various configurations and compare the results from two different towers. Learn about thermal updrafts and solar thermal energy.
It’s time to have some yummy gummy fun with this awesome bubble gum making kit! Mix up your gum base and then sweeten it with sugar. Next, use the three included flavors to make your gum more delicious than ever. Choose from watermelon, orange, and classic bubble gum — or try them all! Finally, cut it up, package it, and label it with stickers to give away as gifts. While you make these yummy treats, you’ll also learn about the scientific properties of elastic materials. Food ingredients included.
Ages: 6+
Experiments: 5
Piece Count: 10
Manual Pages: 16
Wind is one of the most promising sources of clean, renewable energy available today. With this kit, you can assemble a realistic wind turbine complete with electric generator and adjustable rotor blades that are designed with complex aerodynamic curves to look and work like modern-day wind turbine blades. Then, conduct experiments to optimize the turbine’s performance by adjusting the angle of the blades and discover how to use the wind turbine to light up an LED and charge a rechargeable battery. Convert the generator into an electric motor and assemble a small electric car to demonstrate a tangible application for the stored electricity.
The full-color, 32-page manual offers illustrated instructions and scientific information that explores the different types of wind turbines and windmills, the history of this technology, and how wind energy can be used to power homes and electric cars.
Ages: 8+
Experiments: 5
Piece Count: 38
Manual Pages: 32
• Build a realistic wind turbine to harness power out of thin air.
• Assemble a wind turbine complete with electric generator and adjustable blades
• Conduct experiments to optimize its performance by adjusting the blades
• Convert the wind turbine into an electric fan by using the electric generator
• Build three additional models with the parts included
• Conduct more than 20 experiments with your wind turbine
Build a working wind turbine to harness power out of thin air. Wind is one of the most promising sources of clean, renewable energy available today. Wind energy has been used for centuries to pump water and crush grain in windmills, and is now increasingly being used to generate electricity to power our modern world. Assemble a wind turbine complete with electric generator, adjustable rotors, and wind speed indicator. Conduct more than 20 experiments with your wind turbine. Use the wind turbine to generate mechanical power to lift a heavy weight or generate electricity. Learn the physics of force and motion as it applies to wind power technology. Learn how to measure and calculate the different forces acting on the rotor blades. Read about different types of wind turbines and windmills. The full-color, 32-page experiment manual included. Ages 8 and up.
• Perfect for parking lots, crosswalks, and pedestrian walkways
• Can be used with any size PVC traffic cone
• In an immediate situation, deploy a bar - placed between two traffic cones
• Use to create a quick and temporary visible barrier
• Bar expands from 3.35' to 6.6'
• Includes two rings for hanging any of our 24" x 8" plastic signs shown below
• Color: Yellow/Black, Red/White or Orange/White
The Retractable Cone Bar is perfect for parking lots, crosswalks, and pedestrian walkways. The Retractable Cone Bar can be used with any size PVC traffic cone. In an immediate situation, deploy a bar and place it between two traffic cones to create a quick and temporary visible barrier. Cone Bar expands from 3.35' to 6.6'. Retractable Cone Bar includes two rings for hanging any of our 24" x 8" plastic signs.
The design of the Spillnot uses the principles of Newtonian physics to keep the liquid in the container. The flexible handle and location of the suspension point above the center of the tray ensure that the forces on the liquid are always directed toward the supporting tray, even when the tray is in motion. Sideways forces usually responsible for spills are not transmitted to the tray by the flexible handle. Radial forces generated during swinging motion only force the liquid into the container more firmly. An inexpensive demonstration to intrigue students and challenge their analytical powers! Includes activity guide. 5" x 5" x 9". Weight: .25 lbs.
The design of the Spillnot uses the principles of Newtonian physics to keep the liquid in the container. The flexible handle and location of the suspension point above the center of the tray ensure that the forces on the liquid are always directed toward the supporting tray, even when the tray is in motion. Sideways forces usually responsible for spills are not transmitted to the tray by the flexible handle. Radial forces generated during swinging motion only force the liquid into the container more firmly. An inexpensive demonstration to intrigue students and challenge their analytical powers! Includes activity guide. 5" x 5" x 9". Weight: .25 lbs.
Excellent reference collections and a valuable aid in identifying and comparing common and rare rocks and minerals. These mounted collections display common minerals and igneous, sedimentary and metamorphic rocks. Specimens are 1/2"-1". Rocks and Minerals Study Guide included. Grades 5-12. Ages 10-18.
Partial Immersion, Double Scale Range -20/110 degrees C and 0/230 degrees F, Scale: 1 Degree C, 2 Degree F, 300mm Length Partial immersion is best for most applications. These thermometers are calibrated to read correctly when only 3" of the stem is immersed in the liquid being measured. Total immersion thermometers are calibrated for use when the entire liquid column is totally immersed in the substance being measured and should be used under those circumstances. All of our thermometers are made to SAMA specifications for ranges and accuracy. In addition, each of our thermometers has a number of extra quality features built into each one: REINFORCED BULBS, to prevent breakage, RING TOPS, for submersion, NON ROLL CAPS, SCALES PRINTED INTO THE GLASS, rather than on the surface so they never wear off.
Partial Immersion, Double Scale Range -20/110 degrees C and 0/230 degrees F, Scale: 1 Degree C, 2 Degree F, 300mm Length Partial immersion is best for most applications. These thermometers are calibrated to read correctly when only 3" of the stem is immersed in the liquid being measured. Total immersion thermometers are calibrated for use when the entire liquid column is totally immersed in the substance being measured and should be used under those circumstances. All of our thermometers are made to SAMA specifications for ranges and accuracy. In addition, each of our thermometers has a number of extra quality features built into each one: REINFORCED BULBS, to prevent breakage, RING TOPS, for submersion, NON ROLL CAPS, SCALES PRINTED INTO THE GLASS, rather than on the surface so they never wear off.
Partial Immersion, Single Scale Range -20/110 degrees C, Scale: 1 Degree, 300mm Length Partial immersion is best for most applications. These thermometers are calibrated to read correctly when only 3" of the stem is immersed in the liquid being measured. Total immersion thermometers are calibrated for use when the entire liquid column is totally immersed in the substance being measured and should be used under those circumstances. All of our thermometers are made to SAMA specifications for ranges and accuracy. In addition, each of our thermometers has a number of extra quality features built into each one: REINFORCED BULBS, to prevent breakage, RING TOPS, for submersion, NON ROLL CAPS, SCALES PRINTED INTO THE GLASS, rather than on the surface so they never wear off.
Partial Immersion, Single Scale Range -20/110 degrees C, Scale: 1 Degree, 300mm Length Partial immersion is best for most applications. These thermometers are calibrated to read correctly when only 3" of the stem is immersed in the liquid being measured. Total immersion thermometers are calibrated for use when the entire liquid column is totally immersed in the substance being measured and should be used under those circumstances. All of our thermometers are made to SAMA specifications for ranges and accuracy. In addition, each of our thermometers has a number of extra quality features built into each one: REINFORCED BULBS, to prevent breakage, RING TOPS, for submersion, NON ROLL CAPS, SCALES PRINTED INTO THE GLASS, rather than on the surface so they never wear off.
Partial Immersion, Single Scale Range -20/150 degrees C, Scale: 1 Degree, 300mm Length Partial immersion is best for most applications. These thermometers are calibrated to read correctly when only 3" of the stem is immersed in the liquid being measured. Total immersion thermometers are calibrated for use when the entire liquid column is totally immersed in the substance being measured and should be used under those circumstances. All of our thermometers are made to SAMA specifications for ranges and accuracy. In addition, each of our thermometers has a number of extra quality features built into each one: REINFORCED BULBS, to prevent breakage, RING TOPS, for submersion, NON ROLL CAPS, SCALES PRINTED INTO THE GLASS, rather than on the surface so they never wear off.
Partial Immersion, Single Scale Range -20/150 degrees C, Scale: 1 Degree, 300mm Length Partial immersion is best for most applications. These thermometers are calibrated to read correctly when only 3" of the stem is immersed in the liquid being measured. Total immersion thermometers are calibrated for use when the entire liquid column is totally immersed in the substance being measured and should be used under those circumstances. All of our thermometers are made to SAMA specifications for ranges and accuracy. In addition, each of our thermometers has a number of extra quality features built into each one: REINFORCED BULBS, to prevent breakage, RING TOPS, for submersion, NON ROLL CAPS, SCALES PRINTED INTO THE GLASS, rather than on the surface so they never wear off.
Total Immersion, Double Scale Range -20/110 degrees C and 0/230 degrees F, Scale: 1 Degree C, 2 Degree F, 300mm Length Partial immersion is best for most applications. These thermometers are calibrated to read correctly when only 3" of the stem is immersed in the liquid being measured. Total immersion thermometers are calibrated for use when the entire liquid column is totally immersed in the substance being measured and should be used under those circumstances. All of our thermometers are made to SAMA specifications for ranges and accuracy. In addition, each of our thermometers has a number of extra quality features built into each one: REINFORCED BULBS, to prevent breakage, RING TOPS, for submersion, NON ROLL CAPS, SCALES PRINTED INTO THE GLASS, rather than on the surface so they never wear off.
Total Immersion, Double Scale Range -20/110 degrees C and 0/230 degrees F, Scale: 1 Degree C, 2 Degree F, 300mm Length Partial immersion is best for most applications. These thermometers are calibrated to read correctly when only 3" of the stem is immersed in the liquid being measured. Total immersion thermometers are calibrated for use when the entire liquid column is totally immersed in the substance being measured and should be used under those circumstances. All of our thermometers are made to SAMA specifications for ranges and accuracy. In addition, each of our thermometers has a number of extra quality features built into each one: REINFORCED BULBS, to prevent breakage, RING TOPS, for submersion, NON ROLL CAPS, SCALES PRINTED INTO THE GLASS, rather than on the surface so they never wear off.
Total Immersion, Single Scale Range -20/110 degrees C, Scale: 1 Degree, 300mm Length Partial immersion is best for most applications. These thermometers are calibrated to read correctly when only 3" of the stem is immersed in the liquid being measured. Total immersion thermometers are calibrated for use when the entire liquid column is totally immersed in the substance being measured and should be used under those circumstances. All of our thermometers are made to SAMA specifications for ranges and accuracy. In addition, each of our thermometers has a number of extra quality features built into each one: REINFORCED BULBS, to prevent breakage, RING TOPS, for submersion, NON ROLL CAPS, SCALES PRINTED INTO THE GLASS, rather than on the surface so they never wear off.
Total Immersion, Single Scale Range -20/110 degrees C, Scale: 1 Degree, 300mm Length Partial immersion is best for most applications. These thermometers are calibrated to read correctly when only 3" of the stem is immersed in the liquid being measured. Total immersion thermometers are calibrated for use when the entire liquid column is totally immersed in the substance being measured and should be used under those circumstances. All of our thermometers are made to SAMA specifications for ranges and accuracy. In addition, each of our thermometers has a number of extra quality features built into each one: REINFORCED BULBS, to prevent breakage, RING TOPS, for submersion, NON ROLL CAPS, SCALES PRINTED INTO THE GLASS, rather than on the surface so they never wear off.
Total Immersion, Single Scale Range -20/150 degrees C, Scale: 1 Degree, 300mm Length Partial immersion is best for most applications. These thermometers are calibrated to read correctly when only 3" of the stem is immersed in the liquid being measured. Total immersion thermometers are calibrated for use when the entire liquid column is totally immersed in the substance being measured and should be used under those circumstances. All of our thermometers are made to SAMA specifications for ranges and accuracy. In addition, each of our thermometers has a number of extra quality features built into each one: REINFORCED BULBS, to prevent breakage, RING TOPS, for submersion, NON ROLL CAPS, SCALES PRINTED INTO THE GLASS, rather than on the surface so they never wear off.
Total Immersion, Single Scale Range -20/150 degrees C, Scale: 1 Degree, 300mm Length Partial immersion is best for most applications. These thermometers are calibrated to read correctly when only 3" of the stem is immersed in the liquid being measured. Total immersion thermometers are calibrated for use when the entire liquid column is totally immersed in the substance being measured and should be used under those circumstances. All of our thermometers are made to SAMA specifications for ranges and accuracy. In addition, each of our thermometers has a number of extra quality features built into each one: REINFORCED BULBS, to prevent breakage, RING TOPS, for submersion, NON ROLL CAPS, SCALES PRINTED INTO THE GLASS, rather than on the surface so they never wear off.