While most homes have a pre-wired doorbell for the front entrance, for those that don't, using this wireless door chime module by Honeywell is a great solution. Other excellent applications would be for apartments, travel trailers, back entrances, garages, dorm rooms and offices. The bell push unit communicates with the chime module via radio frequency (RF) so no wires are required. There are multiple sounds available and tunes can be programmed to individual bell pushes (if others are added) to identify which doorbell is ringing. Additionally, there are visual indicators on the chime module which helps out those that are hard of hearing. The receiver chime unit can be free standing so you can take it wherever you go in the house, or it can be wall mounted with the included hardware. The bell push module is rated for outdoor use and has a UV resistant plastic housing with a rainproof push button. It can be mounted with included screws or double-sided tape. Each push module has also been individually coded to prevent interference with other transmitters such as PIR movement detectors and telephone ring detectors. The chime module requires three AA batteries for operation, sold separately.Accessories The Honeywell Premium Portable Wireless Door Chime also has the ability to activate via a Honeywell Wireless Battery Powered Motion Sensor (up to two can be used) as a perfect security add-on that will trigger your chime module to alert you when movement has been detected. can be used indoors to monitor specific rooms; alternatively, this product has been built to withstand harsh environmental elements making it suitable for the outdoors. Door Chimes There are three door chimes available: # Ding Dong # St. Clements # Westminster