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Door contact sensor BLOW 4926# (reed switch) — magnetic door/window sensor, normally closed
Summary description:
BLOW 4926# is a door/window magnetic contact sensor (reed switch) designed to detect open or closed state of doors and windows. The normally closed contact changes state when the magnet moves away. It is intended for use in basic alarm and security systems, access control setups, and DIY monitoring where compact magnetic sensing is required.