eWeLink 433Mhz Door Window Alarm Sensor

Features:
*With low battery remind function
*Low-consumption chip design, which can make it work long time.
*High Sensitivity. Excellent design, tiny and fashion. Easily install with stickers.
*Simply attach one piece to your door or window, and attach the other piece to the door or window frame.
*Ideal intrusion warning for homes, apartments, mobile homes, dorms, offices, hotel rooms, garages, etc.