No Battery Required - The wireless doorbell never need battery for use. Self-powered push button converts for kinetic force into electric energy, no batteries required Long Range - Operating range up to 1,000ft/300m in open area ensures you to hear the bell and answer the door in time Waterproof Design - IP55 dustproof and waterproof rating; works between -4 °F to 140 °F; withstands various harsh weather conditions Multiple Volume Option - There are 52 different ring tones with 4 levels of adjustable volume from 0 dB to 110 dB. Flashing light with audio a-lert indicators which is easy for people including the hearing impaired to notice. The self powered doorbell has CE, FCC,RoHS certifications Built-in LED Indicator - Our wireless doorbell receivers and transmitters feature LED indicators that creates visual alerts for the hearing impaired, Weight: 0.330693393 Pounds, Manufacturer: Zambuph