MoKo Wireless Self-Powered Doorbell, [ No Battery Required ] for Receiver / Transmitter, Plug-in Push Button with 32 Chimes, 3-Level Adjustable Volume, Work Over 300-feet(100m) Range, WHITE 32 different ring tones. Operating range of 100m in open area. 3 levels of adjustable volume from 25db to 105db. IP44 weatherproof (Remote transmitter button, acceptable for outdoor use). Self-powered doorbell, no batteries required for main receiver or transmitter. Easily plug (US Standard) receiver into an electrical outlet. CE, FCC, RoHS certified. Screws and double-sided adhesive tapes included for easy installation of the transmitter. Elegant, simple and stylish surface looks pretty high-end. ABS material, anti-burn and impact resistance. Durable & Reliable: This wireless doorbell have a rated durability of 200,000 uses.