To prevent the intruders come in from the doors or windows. It will send alarm signal to the alarm host immediately once the door or window was opened illegal; Technical Parameter: With 2262 encode IC, 433MHZ, 4.7M; Distance: indoor >/= 30m, outdoor >/= 100m (with no obstacle); Battery: 12V 23A. capacity 50MA, with 10 month lifetime; Working current: standby = 16uA, triggered = 19uA; Working temperature: -10~+60'C; Size: emitter 66 x 35 x 14MM, magnetic stripe 66 x 14 x 14MM; Color: creamy-white