| This Wireless USB Doorbell Features a professional waterproof design, can penetrate through 3-4 walls, with a range of up to 150 meters in open areas. It has 3-level volume adjustment and 38 music options for personalization. Ideal for use in villas, apartments, offices, shops, warehouses, and more. Features: Wire-free, plug and play, easy to use. Can penetrate through 3-4 walls, with a range of up to 150 meters in open areas, strong and stable signal. 3-level volume adjustment and 38 music options for personalization, customizable to your preferences. Anti-interference and no false ringing, ensuring normal use. Professional waterproof design, suitable for various places. Specifications: | |