No batteries required: our wireless doorbell transmitter uses unique PUSH RF technology When you press the button, kinetic energy is converted into an electrical signal that rings at your wireless door No more batteries to worry about: more practical, more energy efficient and more useful than the old ones Long radio range: the radio range is 150 metres, so you never lose a visitor, even if you're only a few rooms away or on another floor Ideal for families, large houses, warehouses, offices, etc You can also use it to exercise your dog, quieten your classroom and as an emergency device for the elderly, pregnant women, the sick, etc 45 beautiful chimes and melodies: this wireless doorbell offers 45 classic melodic chimes with adjustable volume control and a wide choice to suit your needs 4 adjustable volumes from 0dB to 90dB, loud enough for seniors to listen to Enjoy pleasant melodies when someone rings your doorbell LED display gives you a visual form of notification (a great feature for the hearing impaired) Waterproof protection rating IP44 for the transmitter Made of ABS, non-toxic, safe and recyclable Can be used in temperatures between -20 C and -65 C, withstands all kinds of bad weather, sun, rain, snow Freezing etc Widely used in homes, offices, hotels, villas, hospitals, offices, flats, schools and other appropriate items Easy to handle. Convenient and user-friendly design for a better user experience Simply stick the wireless doorbell next to the door with the double-sided tape provided or fix the cover to the wall with screws and plug the receiver into an electrical outlet.