No Battery Needed: Our wireless doorbell transmitter uses unique PUSH-RF technology. Pressing the button converts kinetic energy into an electrical signal, wirelessly ringing your doorbell. No more battery worries! Waterproof IP44 & Temperature Display: The IP44-rated waterproof transmitter, made from non-toxic, safe, and recyclable ABS, operates between -20 and 65℃, withstanding harsh weather. The LED temperature display shows Celsius/Fahrenheit when the receiver isn't ringing, doubling as an indoor thermometer. 38 Beautiful Chimes & Melodies: Offers 38 classic melodic chimes with adjustable volume, catering to your preferences. Four adjustable volume levels from 0dB to 100dB are loud enough for the elderly to hear. The LED indicator provides a visual alert, great for the hearing impaired. Long Wireless Range: With a 150M/500FT wireless range and two plug-in receivers included, it won't interfere with other equipment. You'll never miss a visitor, even rooms away or on another floor. Perfect for homes, offices, hotels, villas, hospitals, apartments, schools, and more. Easy to Use: Practical and user-friendly design. Simply peel off the film on the transmitter and stick it by your door, then plug the receivers into outlets. All URESMAT wireless doorbells can be paired and controlled together. Contact us for assistance.