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 practical, more energy-saving and more practical than the old one. IP44 waterproof & Temperature Display: IP44 Rating Waterproof design of the transmitter, made of ABS, non-toxic, safe and recyclable, which can operate at temperatures between -20℃ and 65℃, and withstand various harsh weather conditions. LED temperature display screen, Celsius/Fahrenheit temperature appears when receiver is not ringing, can be used as indoor thermometer. 38 Beautiful Chimes and Melodies: Offers 38 classic melodic chimes with control adjustable volume and a diverse selection to meet your needs. 4 adjustable volume levels from 0dB to 100dB, which is loud enough for old people to hear; enjoy pleasant melodies whenever someone rings your doorbell. The LED indicator