| Waterproof Transmitter And Receiver, Self-powered Doorbell, Smart 300m Remote. Features Battery-free Wireless Doorbell, Driving Wireless Signal by Pressing Power Generation, No Battery, No Wiring, Simple Installation, Green and Environmental Protection, the Appearance is Minimalist Design, Simple and Generous, and the Shape is Round and Beautiful. BM3FS Can Be Used with Receiving Devices Such As Wireless Receivers/smart Switches for Remote Control of Electrical Equipment, Which Can Easily Realize Single Control, Dual Control, Multiple Control and Mutual Control. It is Not Only an Application Doorbell, but Also Can Be Used in Various Fields Such As Switches and Pagers. Function 1. Self-powered … | |