Compact door and window magnetic sensor pairs for wired or wireless alarm panels. Magnets sit close to the sensor in normal condition, keeping the reed switch closed and completing the circuit. When the magnet moves away, the switch opens and the alarm panel detects the change. Key benefits Simple integration: connects directly to the GND and N.C ports of most wired or wireless alarm control panels. No external power supply required. Reliable detection: magnets and reed switch operate as a normally closed contact. Magnet present equals closed circuit; magnet moved away equals open circuit and a trigger for the alarm. Long life and durable performance: rated for 1 million switching cycles to support long term home or office security needs. Compact and practical: small sensor pairs fit inside door and window frames for discreet installation. Clear compatibility note: not suitable for iron doors because iron can reduce magnetic strength and interfere with operation. Specifications Working distance: 15 mm plus 5 mm Switching voltage: 100 VDC Load current: 300 mA Switch output: NC normally closed Mechanical life: 1,000,000 cycles Package weight: 91 g Package contents: 10 pairs door window sensor How it works Normal state: magnet close to sensor keeps the reed switch closed, creating a complete circuit at the N.C contact. Alarm state: when a door or window opens, the magnet separates from the sensor, the reed switch opens, and the alarm control panel registers the change. Typical applications Home security: install on entry doors and ground floor windows to detect unauthorized opening. Office and small business: monitor internal doors, storage rooms, or cabinets connected to a wired or wireless alarm panel. Rental properties and vacation homes: provide basic intrusion detection without additional power wiring. What to check before installation Confirm your alarm panel provides GND and N.C terminals for direct connection. Avoid mounting on iron or steel door frames where magnetic performance may be reduced. Observe the specified working distance for reliable operation. Package includes 10 pairs of door window sensors ready for setup with compatible alarm control panels.