Door open alert home security business protection device

Free security solution for home and business protection at https://www.vedard.com/forum
Wireless rolling shutter garage door magnetic contact
MD-212R meian tech FOCUS wireless rolling door contact for garage security.
Smart home wireless security system.
Functions and Specification:

1.Micro-power dedicated CPU
2.Low battery checking circuit, the LED will ON when low battery
3.Send report when shutter door is not closed.
4.Starting control distance: