YIROKA Digital Wireless Doorbell (Encrypted Radio Signals System, 2 Door Chimes - 1 Waterproof Remote Control) with 48 Chime Tones & LED Flashing Indicator Digital encrypted radio signals system, prevent interference from others / neighbors doorbells or radio signal devices; Energy efficiency design; IP44 rated waterproof remote control (transmitter unit) 48 different melodic sounds for selection; Plays ding dong chime; 4 levels of adjustable sound volume; Wireless transmission to master unit Compact design; No wiring or drilling; Easy installation; Wireless doorbell can be placed / carried with you 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: 3.66" x 3.19" x 1.06" (93mm x81 mm x 27mm) Remote control: 3.54" x 2.01" x 0.78" (90mm x 51mm x 20mm); Power: Doorbell main unit: 3 x AAA batteries (not included) Remote control: 1 x 23A 12 V battery (included); FCC, CE, and RoHS certified