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Door contact sensor BLOW 4921# model HO-03C white, magnetic reed switch
Summary description:
Wired door contact sensor BLOW 4921# (HO-03C) in white. Magnetic reed-switch sensor designed to detect opening and closing of doors or windows and integrate with alarm or security systems. Compact housing and two-part design allow easy surface mounting on frames; suitable for residential and commercial intrusion detection and access monitoring.