Digital Wireless Doorbell (Encrypted Radio Signals System, 2 Chimes - 1 Waterproof Remote Control) with 4 Chord 20 Musics & LED Flashing Indicator Digital encrypted radio signals system, prevent interference from others / neighbors doorbells or radio signal devices; Energy efficiency design; Waterproof remote control (transmitter unit) 20 different melodic sounds for selection; Plays ding dong chime; Wireless transmission to master unit No wiring or drilling; Easy installation; Wireless doorbell can be placed anywhere you want; Hear the door chime in any room; Never miss a visitor or delivery again Useful in home, office, or commercial buildings; LED indicator flashes (chime main units) when bell rings; Advanced technology; New sounds; Premium quality; Double sided self adhesive tape included for remote mounting Dimensions: Doorbell main unit: 4.72" x 3.07" x 1.30" (120mm x 78mm x 33mm) Remote control: 3.15" x 1.78" x 0.91" (80mm x 45mm x 23mm); Power: Doorbell main unit: 3 x AA batteries (not included) Remote control: 1 x 23A 12 V battery (included)