Yaho-mall the Clapper Sound Activated Switch on / Off By Hand Clap Electronic Gadget The clapper is a sound activated on and off switch for applicances. While in the HOME mode, the clapper can operate either one or two applicances by clapping two times to operate the first applicance and three times to operate the second applicance. (More details please refer to the instruction manual.) While in AWAY setting, the clapper can serve as a limitted function security device -- almost any noise will turn on the connected applicance(s) to discourage potential instruders, also, it is convenient for temporaily turnign on a light when entering a dark room such as a garage or a basement. You can adjust your clapper to respond to soft or loud claps as well as adjusting for the noise level in your room. (More details please refer to the instruction manual)