Features:
*low-consumption design, which makes it work a long time
*remote control operation makes it easy to operate
*it has the function of arm, disarm, emergency alarm, and doorbell.
*knocking the door or window can trigger the alarm.
*105db ultra-loud alarm design, effectively frighten thieves who want to break into your home.
*installation with double-side adhesive, easier to install
uses battery: 2*aaa