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.