No Batteries Required: Our wireless doorbell transmitter adopts unique Push RF technology. When pressing a button, the kinetic energy is converted into an electrical signal to wirelessly knock on the door. More batteries are a problem. More practical, more energy efficient and more functional than the old one.;45 Beautiful Chimes and Melodies: Offers 45 classic melodic chimes with volume adjustment and many options to meet your needs. 4 adjustable volume levels from 0~110 DB, enough for the elderly to hear; Every time someone knocks on your door, enjoy the wonderful melody. The LED indicator gives you a visual form of notification (a great feature for the hearing impaired).;IP44 Waterproof: The IP44 waterproof transmitter is designed by ABS, non-toxic, safe, recyclable, can work in temperatures from -20℃ to 65℃, and can withstand all kinds of adverse weather conditions, sun, rain, snow, frost, etc. It is widely used in homes, offices, hotels, villa, hospital, office, apartment, school and other related areas.;Long Range Wireless: The wireless range is 150m/500ft and includes 2 plug-in receivers that won't interfere with other devices in your home or neighbors; Make sure you never miss a visitor, even if you are located in several rooms or on another floor. for large homes, warehouses, offices, etc.;Easy to Use: Convenient and user-friendly design for a better user experience. Simply attach the doorbell next to the door with the included double-sided tape or attach the cover to the wall with screws. Then plug the receiver into a power outlet.