Strong plastic construction. These Buzzers are an essential electrical part for use in Physics electrical circuits and Sound experiments and other general lab use. Buzzer dia. 1.15" (29mm) x 0.58" (14.8mm) thick. Base 1.89" (48mm) long, with two holes 0.13" (3.48mm) dia. for mounting. Connecting wire 4" (100mm) long.