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Door contact sensor BLOW 4557# (reed switch) HO-03G brown
Summary description:
Wired door contact sensor BLOW 4557# (HO-03G) in brown. A simple reed-switch style sensor designed to detect opening and closing of doors or windows. Suitable for use with alarm systems, home security setups, and access monitoring. Small form factor for discreet mounting on frames and sashes; provides a contact closure signal when the magnet is separated.