Description:1.NO means Normally Open: when the magnet separate, the circuit is conductive( light on );When the magnet together, the circuit is not conductive ( light off ).When make order,pls check carefully! 2.NC means Normally Closed: when the magnet separate, the circuit is not conductive( light off );When the magnet together, the circuit is conductive ( light on ).When make order,pls check carefully!3.These are the door contact sensors that are in use with any and all commercial or residential card access systems as well as all security burglar alarm system.4.Work as an anti-theft alarm, perfect for metal door and window. Specification:Product Name: Magnetic Door SwitchModel: RC-33Contact Type: NO (Normally Open)Max. Sensor Sensitivity: 10mmMax. Current: 0.5AMax.
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