Sound Activated Switch
Ultra-sensitive switch can respond to a whisper or a loud clap. Easily adjust sound sensitivity. Choice of three modes of operation. 4-1/2"L x 2-1/4"W x 1-1/4"H. Operates with one 9-V Battery (not included).
Operates as a momentary switch. The connected device stays on as long as switch detects sound.
Operates as an on/off switch. Connected device goes on with the first sound and stays on until it detects another sound, which turns it off.
Operates as a timed switch. Connected device goes on for a set amount of time (1 - 120 seconds) when switch is activated, then turns off at the end of that time.
More information: https://www.schoolhealth.com/sound-activated-switch