400M / 1,312FT Ultra-Wide Wireless Range: Includes two plug-in ringer receivers; does not interfere with other devices in your home or at your neighbors; even if you're a few rooms away or in another location, you can rest assured that you won't miss any visitors. 52 Ringtones to Choose From: The ringtone receiver provides rich, clear sound; 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 of the doorbell set uses a CR2032 lithium battery, which provides a 3-year life; IP55 dust and water resistance; operates at temperatures from -20°C to 60°C; can withstand harsh 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. Simply plug the receiver into the socket. Memory Function: The doorbell radio remembers your last selected melody and assigned volume even after a power outage; you do not need to reset previous settings; convenient and user-friendly design enhances your user experience.