1~10Pcs Magnetic Wireless Security Entry Window Door Burglar Alarm Device Sensor

Open the door and see if the siren sounds. 1/2/4/6/8/10X Alarm Kit (alarm unit & magnetic sensor). Sensor type: alarm. Magnetic sensor: 9X3X2CM. Alarm type: sound. Alarm unit: 4.5X1.5X1.5CM. Fix the host to the door / window with double-sided tape.

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