Mount the door chime button (mounting hardware and foam tape included) at the desired entrance and plug the chime receiver into any indoor outlet. 2-1/4 in speaker provides excellent sound. Adjustable volume control. Plays thirteen sounds selected on frontof button. 32 changeable codes prevent interference. Button is weatherproof for safe outdoor installation, use indoors or out, with an operating temperature from -30 to 130° F. Includes a 10-year lithium button battery. Up to 150 ft operating range.