Require no batteries, can’t cause the water and soil pollution.
The doorbell transmitter is embedded with micro generator which can create energy when press. No battery inside. Energy saving.
Wireless
Never change batteries, more convenient. No need to change the battery frequently, save money, and eco-friendly.
Signal passes through doors, walls and floors. Transmission range is up to 150 meters in the open air. The volume is big enough; you can hear it in any room.
38 chime sounds, built-in amplifier, good sound quality makes it pleasant to hear.,
Easy installation, the transmitters can be mounted with screws or double faced tape. The receivers plugs into any standard wall outlet.