Easy to install, no wiring required
When rung, you will both get a notification on your phone,
as well as a chime sound inside of your house.
Watch remotely anytime, anywhere
Mobile normal alarm, APP real-time reminder

Product Name: Smart Doorbell
Model: M20
Power supply mode: 18650 battery power supply (uncharged)
Power supply voltage: 3.7 (V)

Please Note: 

Batteries NOT included.