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Door contact sensor BLOW 4931# (reed switch) model HO-03D, wired magnetic door/window sensor
Summary description:
Wired magnetic door/window contact sensor BLOW 4931# (HO-03D) is a reed-switch type detector for monitoring open/closed state of doors or windows. Designed for integration with alarm and security systems, it provides a simple magnetic contact and compact mounting. Typical use includes perimeter protection, entry monitoring and system arming/disarming triggers.