Cyelee(TM) 433MHz Portable Rainproof Wireless digital Doorbell with 2 Remote Button Transmitter and 1 Plugin Receivers Operating at over 500-feet Range with Over 36 Chimes, No Batteries Required for Receivers,For Kids Room/Bedroom/Apartment/Office(2 Button + 1 Chimes) Simple/elegant design,So easy to use.Door chime can be plugged into a standard electrical outlet in your home,Transmitter can be attached to the wall using double-sided adhesive tapes. Ultra-low-power design:No LED light,Power consuption is 0.1W,energy saving,work for long time. 300m/1000ft long distance remote control, stable signal.Work Frequency:433.92MHz Offers a total of 36 chime tones and 3 levels of adjustable sound volume plus a silent mode. Remote transmitter button is rated IP33 weatherproof and acceptable for outdoor use. Easily plug receiver into an electrical outlet (no batteries required for main receiver). CE, FCC, RoHS certified.