QWORK MC-31 NC Wired Magnetic Door Window Contact Sensor, 20 Pack with 80 Screws, Surface-Mount White Plastic Alarm Reed Switch for Doors Windows Cabinets

About this item

• NC MAGNETIC CONTACT SENSOR: Surface-mounted wired magnetic door/window contact sensor (MC-31, NC). Magnet close = circuit conductive; magnet separated = circuit disconnected—ideal for wiring into security alarm loops.
• 8MM ACTUATION GAP: Designed for an actuation distance of 8mm ±18mm to help maintain reliable open/close detection during everyday door and window movement; suited for common home security system wiring.
• SURFACE-MOUNT FOR QUICK RETROFIT: Screw-on design for fast installs on doors, windows, cabinet doors, and storage rooms—use for perimeter monitoring where recessed/drilled contacts aren’t convenient.
• MATCHED HOUSING & HARDWARE: White plastic housings blend with frames; mounting hole diameter 5.8mm. Set includes 20 sensor/magnet pairs plus 80 screws to equip multiple openings in one project.
• INSTALLATION NOTES: Keep the sensor and magnet aligned and on the same plane; verify the gap stays within the actuation range across the full swing. Package includes 20 sets (64×12×12mm & 64×20×12mm) and screws.