Specification Alarm Volume: 90dB Battey life: over 12 months Including items: alarm main unit, magnetic sensor Detector mode: magnetic door sensor Battery: 1.5V AG13 or LR44(included),low battery test button. Size : 55mm*12mm(magnetic sensor) , 65*30*20mm (main unit) Triggered Immediately Alarm will be triggered immediately once you separate two parts.90 db loud alarm helps deter intruder and possibly notifies neighbors/homeowner, also helps notify you if visitors/children/pet or others are coming/going when you are at home.
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