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: 250 mm / 984 inchMaximum Current: 0.5AMaximum Voltage: 0-100VSensing Distance: 20-30 mm / 0.79-1.18 inchMagnetic Sensor 1: 3.2 x 1.45 cm / 1.26 x 0.57 inchMagnetic Sensor 2: 3.2 x 1.45 cm / 1.26 x 0.57 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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