Self Powered Wireless Doorbell

Features: - Self-powered electricity, pressing the button and force into electric energy.  - No wire no battery required in transmitter, just plug and use with receiver.  - 5-level sound volume adjustable, choose your favorite ringtone.  - One transmitter can pair with many receivers with 36 of ringtone.  - Smart chipset with memory function about the set ringtone storage after powering off.  - The Doorbell Wi-Fi version support Mi Home APP control, and smart devices linkage.  - Durable flame retardant matte surface, simple and fashionable design.  - Easy installation, no need complex steps, just sticking and start to use. Specification: Product Name: Self-Powered Doorbell transmitter;  WifI: 2.4GHz;  Frequency: 433.92MHz;  Distance: about 50M outdoor;  Transmission frequency: 10dBm;  Operating force: about 700g;  Size: 67*67*19mm;  Weight: 43g;  Product Name: Self-Powered Doorbell receiver;  Host power supply: 110-240VAC;  Plug: US regulations;  Size: 68*68*31mm;  Weight: 74g;  Pack