... products are gsm alarm,mms gsm alarm, IP camera,wireless alarm,power alarm,anti-losing alarm,door/window sensor,etc ... detecting ability.C. Easy to install, absolutely wireless, power supply built-in, wireless telegraph transmitting signal.D. Save power design& ... detector.E. Extending socket built-in, compatible with wireless multi-host.Power supply: 1.5V high alkaline battery. 2500mAHWorking current ...