Waterproof touch doorbell button. Doorbell, alarm, welcome alarm all in one. 38 songs optional, 4 levels adjustable volume. 300 meter receiving distance (in the open area), stable quality is ideal for villas, hotels, schools and other areas. Type: Wireless Doorbell Material: Plastic Model: A10 Operation Range: 300m in Open Area Melody: 38Pcs Volume: 4 Levels (20-85dB) Battery Type: 1 x 12V 23A Battery (Not Included) Power source: AC 100-240V Plug Type: US Plug, UK Plug, EU Plug (Optional) Features: Wireless, Waterproof, 4 Levels, Built-in Music Size of Transmitter: 7.5cm x 5.1cm x 2cm/2.95" x 2.01" x 0.79" (Approx.) Size of Receiver: 9.5cm x 6.5cm x 2.4cm/3.74" x 2.56" x 0.94" (Approx.) Notes: Due to the light and screen setting difference, the items color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement. Package Includes: 1 x Transmitter 1 x Receiver 1 Bag of Screw 1 x Double-sided Sticker 1 x User Manual