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. 45 Beautiful Chimes and Melodies: Offers 45 classic melodic chimes with adjustable volume control and diverse selection to meet your needs. 4 adjustable volume levels from 0dB to 90dB, which is loud enough for old people to hear; enjoy pleasant melodies whenever someone rings your doorbell. The LED indicator gives you a visual form of notification (a great feature for the hearing impaired). IP44 Waterproof: IP44 Rating Waterproof design of the transmitter, made of ABS, non-toxic, safe and recyclable, can Operate at temperatures between -20 and 65, and withstand various severe weather conditions, sunshine, rain, snow, frost etc. Widely used for home, office, hotel, villa, hospital, office, apartment, school and other suitable fields. Long Wireless Range: With 150M/500FT wireless range, 2 plug-in receivers included , do not interfere with other equipment in your home or those of your neighbors; ensures that you will never miss a visitor, even if you are a few rooms away or on another floor. Ideal for large homes, warehouses, offices, etc. Easy to Use: Convenient and easy to use design for better user experience. Simply stick the doorbell next to your door using the included double-sided tape or use the screw to mount the cover to the wall. then plug the receiver into a power outlet. All URESMAT wireless doorbells can be re-paired and controlled together.