The door contact sensor is a magnetic field electrical switch that provides a high-pitched alarm when someone opens a door or window when it is closed, thus protecting your home.SpecificationColor: GreyMaterial: Zinc AlloySize: Cable Length: 380 mm / 14.96 inchMaximum Current: 0.5AMaximum Voltage: 0-100VSensing Distance: 50-70 mm / 1.97-2.76 inchMagnetic Sensor 1: 10.5 x 3.8 cm / 4.13 x 1.5 inchMagnetic Sensor 2: 10.5 x 1.6 cm / 4.13 x 0.06 inchPacking List: 1 x Rolling Door Contact SensorAdvantageRust-proof Material - The wired contact sensor is made of rust-proof and durable zinc alloy, with sensitive response of magnetism and can be used for a long time.
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