Ask your class to identify each of 12 different samples by determining their density. Each cylinder varies in size and density since it is constructed of a different material. All are 1/2" in diameter and vary in length. This kit includes: 12 samples, an attractive wood storage rack coated in linseed oil for protection from wet specimens, and detailed instructions with theory. Samples include: aluminum, brass, copper, acrylic, pyrex, rubber, delrin (plastic), PVC, PTFE, nylon, poplar and oak.