【Easy to Install】Just plug the receiver into an outlet and attach the transmitter to the wall or door frame with the included tape or screws. No hassle with wires 【400M Wireless Range】The penetrating wireless signal can be transmitted up to 400m in an open and accessible space, you will never miss a visitor even if you are several rooms away or on another floor. The doorbell does not interfere with other equipment in your or your neighbors' home 【55 Melodies & 5 Volume Levels】The doorbell receiver with full and clear sound; press the follow or return button to choose between melodies; 5 volume settings with a maximum volume of 110dB; enjoy the pleasant and beautiful ringtones every time someone is at the door 【Waterproof and LED Design】The wireless transmitter is made of superior material and is IP55 waterproof, stable performance is guaranteed for outdoor use. Blue LED on the button and receiver is a visual indication for host and visitors, it is also a fun and accurate design for the hearing impaired 【Memory Function】The wireless doorbell package remembers the last melody and volume level after a power outage; no reset required; designed for particularly practical and easy use for even more comfort 55 ringtones and 5 volumes (0-110dB) 55 different ringtones and 5 adjustable volumes from 0 to 110 dB. It's loud enough. 0 Silent Mode You can turn on silent mode if you don't want to be disturbed. Blue LED Flashes Both the button and the receiver are equipped with indicator lights that flash when someone presses the button, which is a very friendly feature for the hearing impaired and the elderly. Memory Function The built-in memory chip ensures that the doorbell remembers the music and volume you previously set, even if there is a power outage you do not need to reset it. Dustproof and Waterproof (IP55) The waterproof outdoor doorbell button adapts to various climates in DE and works in temperatures from -30℃ to 70℃. High-Performance Battery The doorbell button is powered by a 12V23A battery, which has a lifespan of 1 to 3 years. Expand Your Doorbell System You can expand the coverage of your home doorbell by adding additional transmitters or receivers of the same model, they can be matched with your existing doorbell. There are two installation methods to choose from: 1. Attach the button to the wall or door frame with the included double-sided tape. 2. Attach it with screws (included), but you need a small electric drill to drill holes in the wall. Note: Do not attach the doorbell to a metal surface, as this will reduce its wireless distance.