Ultra-wide wireless range of 400M or 1312FT: includes two plug-in ringer receivers not interfere with other appliances in your house or at your neighbours So even if youre a few rooms away or at another location, you can rest assured that you wont miss any visitors. 52 Ringtones to Choose From: The ringtone receiver provides rich sound and light five adjustable volume levels with a maximum volume of 115 dB press the next or previous button to easily select from 52 songs. high performance transmitters: extremely low power consumption The bell button bell set uses a CR2032 lithium battery, which provides a 3-year lifespan IP55 dust and water resistance Operates at temperatures from -20C to 60C even withstand the harshest weather conditions. EASY SETUP: The wireless doorbell kit can be easily installed by attaching the doorbell button to the wall, no wiring required includes two screws, two anchors, a key and a piece of double-sided tape. 3 Simply plug the plug-in receiver into the socket. Memory function: the doorbell radio remembers your last selected melody and assigned volume even after a power failure You dont need to reset the previous settings Convenient and user-friendly design enhances your user experience.