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Door sensor BLOW 4920# magnetic reed contact HO-03B brown
Summary description:
Magnetic door sensor BLOW 4920# (HO-03B) in brown. A reed-contact type door/window sensor designed for intrusion detection and alarm systems. Consists of a magnet and a switch that closes or opens the circuit when the door or window moves; suitable for mounting on frames for basic contact detection in residential or commercial alarm installations.