Features ---Super loud 90 dB alarm ---Convenience in installation--just peel and stick ---Super environmental suitability and stability ---Dustproof and insect prevention ---Easily mounted by adhesive tape to window or door. Ideal entry warning for homes, apartments, mobile homes, dorms, offices, hotel rooms, garages, and more! ---Magnetic sensor switch detects entry protecting your home or office whether you are in or out ---Operated by 3pcs of 1. 5V LR44 / AG 13 button cell ( included ) Specifications ---Sensor type: Magnetic ---Alarm type: sound ---Material: plastic ---Color: White ---Size: 2.5 x 1.3 x 0.8 in ---Power: 3x LR44/Ag13 Battery (included) Operationg Instructions 1--Use the double-side adhensive tape to fix the main unit at the side of the door or window.
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