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Door magnetic contact sensor BLOW 4927# HO-03G white, reed switch door/window sensor
Summary description:
Wired door/window magnetic contact sensor BLOW 4927# (HO-03G) in white. A reed switch style contact sensor designed to detect opening or closing of doors and windows. Includes two parts: sensor body and magnet; suitable for use in alarm systems, access control, and intrusion detection where a simple magnetic contact is required.