Wireless doorbell receiver and button. Mount the button in desired location and plug doorbell into any 120 volt AC electrical outlet within operating range. Compact to fit neatly against wall, behind furniture or other out-of-the-way places. Plays 2 sounds - Westminster Chimes and Ding Dong. Red light illuminates when button is working. Up to 75 ft operating range. Uses (2) 3 volt lithium batteries (installed). Works with Carlon 5000 Series doorbells only. 32 selectable codes block interference from outside signals. Mount with screws or double-face tape (included).