4-IN-1 Wireless Entry Home Security Door Window Open Alarm Super loud alarm, volume up to 110dB Durable battery, LR44 battery for 1 years work.(Contain batteries) Four Fuctions;Security alarm fuction, emergence fcnction, doorbell chime fuction and reminding closing door fuction. Universal design, installation simple and easy to use Continuous sales for 5 years , repair rete is less than 0.2% Application:door,window, refrigerator door. Package including: 1 x Magnetic Sensor 1 x Magnetic Stick 2 x 3M Tape 1 x User Manual.
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