Battery free power generation, door opening reminder, horn alarm

Self-Power Wireless DoorbellMultiple choices of

1.58 melodies and 3 volume levels to meet your needs in different occasions;

2. Adopting a 433.92 frequency wireless signal, it has strong penetration and can penetrate 3-4 doors, with a reception distance of up to 150 meters in open areas;
3. Waterproof level IP44;
4. Finger pressing generates electricity without the need for a battery
It can penetrate 3-4 walls and wireless range up to 150 meters in open area,great for large house including willas, apartment,offices,shops,warehouses.etc.