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 suitable fields. Long Wireless Range: With 150M/500FT wireless range, 2 plug-in receivers included , do not interfere with 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 an 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.