5piece set of NC magnetic reed door and window contacts for alarm and security systems Keep doors and windows monitored with compact normally closed reed switches that integrate with common alarm panels and DIY security setups. Each unit uses a magnet and ABS housing to detect open and closed states, giving a simple and effective way to trigger alerts when an entry point is opened. Key benefits Clear function: Normally closed operation closes the circuit when the magnet is aligned and opens the circuit when the door or window is moved, making it easy to detect unauthorized openings. Simple integration: Designed for use with alarm control panels and security devices that accept NC contact sensors, allowing fast retrofit or installations. Durable housing: ABS casing provides impact resistance and stable mounting in everyday indoor and sheltered outdoor environments. Space saving: Low profile, compact form factor mounts discreetly on door and window frames without interfering with operation. Pack of five: Multiple sensors included for monitoring several entry points or covering larger installations. What it solves Adds intrusion detection to doors and windows without running complex electronics. Enables reliable trigger signals for alarms, automation controllers, and monitoring systems using NC contacts. Allows staged upgrades to home security by installing sensors gradually with matching components. Key attributes Type: NC normally closed magnetic reed switch contact Quantity: 5 pieces Housing material: ABS plastic Application: Door and window contact for alarm and security use Compatibility: Works with security panels and devices that support NC contact sensors Mounting: Compact mounting suitable for most frames; can be surface mounted or recessed where space allows Typical use scenarios Home entry points: Install on front, back, or patio doors to trigger an alarm or automation event when a door is opened. Groundfloor windows: Monitor accessible windows and sliding doors to add an extra layer of perimeter security. Small business or storage units: Place on doors, cabinets, or storage room entries to log or alarm unauthorized access. Installation tips Position the magnet and switch so they align when the door or window is closed. Test the sensor operation with your panel to confirm correct NC behavior before final mounting. Use screws or appropriate adhesive fasteners suitable for the mounting surface. This set provides straightforward, nononsense magnetic contacts for reliable door and window monitoring in residential and small commercial security setups.