Mount the battery powered smoke detector transmitter anywhere in your home. Place the receiver in the location you want to be alerted, next to the bed, in the living room, etc. The transmitter detects smoke within a radius of 100’, and sends a signal that flashes a strobe connected to the receiver. This Sidekick receiver will also signal in response to other Silent Call transmitters (door,  phone, sound monitor, carbon monoxide detector, etc.) as well as the smoke detector. Use as many smoke detectors and receivers as you wish. Completely portable. Transmitter uses 9 volt battery (included). Two year warranty. Easy installation, no wiring necessary.