No Battery Required: Our wireless doorbell transmitter uses unique PUSH-RF technology. When you press the button, the kinetic energy is converted into an electrical signal that rings your doorbell wirelessly. No more worrying batteries. More convenient, more energy-saving and more practical than the old one. Waterproof IP44 & Temperature Display: IP44 Waterproof transmitter design, made of ABS, non-toxic, safe and recyclable, can operate at temperatures between -20 and 65, and withstand various harsh weather conditions. LED temperature display screen, Celsius/Fahrenheit temperature appears when the receiver is not ringing, can be used as an indoor thermometer. 38 beautiful chimes and melodies: Offers 38 classic melodic chimes with one control adjustable volume and a diverse selection to meet your needs. 4 volume levels adjustable from 0dB to 100dB, which is loud enough for older people to hear; enjoy pleasant melodies every time someone rings your doorbell. The LED indicator gives you a visual form of notification (a great feature for the hearing impaired). Long Wireless Range: With a wireless range of 150M/500FT, 2 plug-in receivers included, won't interfere not with other equipment in your house or that of your neighbors; ensures that you will never miss a visitor, even if you are a few rooms away or on a different floor. Ideal for home, office, hotel, villa, hospital, office, apartment, school and other suitable fields. Easy to Use: Practical and easy-to-use design for a better user experience. Just tear off the film on the transmitter and stick it next to your door. then plug the receivers into the power outlets.