General description No batteries are required for this innovative wireless doorbell, which utilizes unique PUSH-RF technology to convert kinetic energy into an electrical signal, allowing it to ring wirelessly. This energy-saving and practical solution eliminates the hassle of changing batteries. The doorbell features an IP44 waterproof design, ensuring durability in various weather conditions, and includes a LED temperature display that functions as an indoor thermometer. Technical specifications Wireless range: 150M/500FT Temperature operating range: -20℃ to 65℃ Volume levels: 4 adjustable levels from 0dB to 100dB Material: ABS (non-toxic, safe, and recyclable) Usage Ideal for home, office, hotel, villa, hospital, study, apartment, school, and other suitable fields. Offers 38 classic melody chimes with adjustable volume control. LED indicator provides a visual notification for the hearing impaired. Installation Simply tear off the film on the transmitter and stick it next to your