TECKNET Wireless Doorbell, Self-Powered Doorbell, 0-110db Plug-through Wireless Doorbell Ringer for Homes Classroom, IP66 Waterproof 1300ft Door Chime with Extra Socket, 60 Chimes, LED Light (White)

♬ WILL NOT TAKE UP YOUR SOCKET WIRELESS DOORBELL KIT: The unique plug-in doorbell chime kit is small and nice. The extra socket can be used for any other electrical equipment. Plug the doorbell into the wall socket and then plug appliances into the chime unit as normal. This is the best choice for waterproof wireless doorbells for homes and any other occasions.
♬ AMAZING WIRELESS DOORBELL NO BATTERY REQUIRED: Ditch the traditional house doorbell. 1 transmitter (push button) and 2 receivers(chimes) of this self-powered doorbell don’t require battery. After pressing the push button, it will generate electricity by itself and send a stable signal to the receiver. With this self-powered doorbell, you will no longer worry about frequent battery replacement.
♬ MEMORY FUNCTION & EASY TO INSTALL: Just plug the doorbell chimes into a socket and fix the push button on a wall with the accessories provided; it does not interfere with other equipment in your home or those of your neighbors, and you will never miss a visitor. The doorbell remembers your last melody and volume level after a power outage; no need to reset to your previous settings