Kerui Wireless Doorbell PIR Motion Detect Security Alarm Waterproof Button Smart Home

Wireless Doorbell and PIR Motion Detect Security Waterproof Plug and Play System for Smart Home  Features 57 different ring tones  -:4 levels of adjustable volume from 25db to 85db, Memory function for sound and chime selection Easy to Installation -:Real Plug and Play Operating range of 328 feet. (100 feet in open area） -:Ensures you will never miss a visitor, even if you are a few rooms away or on another floor Different Song Use for Different Mode. Expandable with Connecting Multiple Sensors and Switches as Per Your Requirements. -:Each Wireless Doorbell Can Pair Up to 20 Magnetic Door Alarm Sensors and Each Sensor Can Add Unlimited Receivers.     57 different ring tones 4 levels of adjustable volume from 25db to 85db, Memory function for sound and chime selection   Keep your children safe Alert when your lit