Description:1.NC means Normally Closed:When the magnet together, the circuit is conductive( light on ); when the magnet separate, the circuit is not conductive ( light off ). When make order,pls check carefully!2.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.3.Work as an anti-theft alarm, good for metal door and window. Note: Specification:Product Name: Magnetic Door SwitchContact Type: NC (Normally Closed)Material: ABS (Housing)Wire Type: 1007UL#24AWGColor: White Package Content: Magnetic Door Switch Note: Door magnetic induction can only provide a switch signal to the equipment, which can not directly load the power, nor directly connect the lamp.
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