Seco-Larm SM-204Q/W Surface-Mount Magnetic Door Sensor N.C (Pack of 5)

The Seco-Larm SM-204Q/W is a surface-mount normally closed magnetic contact designed for professional life-safety and commercial security installations. Surface-mount magnetic contacts are a foundational component in perimeter detection systems, providing reliable door and window status monitoring without requiring routing wire through door frames or casings. The normally closed circuit configuration is the industry-standard choice for supervised alarm loops, ensuring that a cut wire or tampered connection triggers an alarm condition rather than going undetected. With Seco-Larm's reputation for quality in the commercial security space, the SM-204Q/W is a dependable choice for integrators and installers building or expanding intrusion detection systems across commercial, institutional, and industrial environments.

Key features & benefits

• Surface-Mount Form Factor — Designed for straightforward installation directly onto door or window surfaces, eliminating the need for recessing or frame modification and reducing installation time on new and retrofit projects alike.
• Normally Closed (N.C.) Circuit Operation — The normally closed configuration integrates seamlessly into supervised alarm loops, ensuring any break in the magnetic field — whether from door opening or wire tampering — generates an immediate alarm condition.
• Genuine Seco-Larm Component — Sourced directly from Seco-Larm, a recognized manufacturer in the commercial security industry, providing confidence in product authenticity and consistent performance across large-scale deployments.