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Door magnetic contact sensor BLOW 4919# HO-03B white — wired door/window sensor
Summary description:
Wired door/window magnetic contact sensor BLOW 4919# (HO-03B) in white. Designed to detect opening and closing of doors or windows via a reed switch (kontaktron). Suitable for integration with alarm and security systems, providing a simple normally closed/normally open input for control panels and home security setups. Compact and mountable on frames and sashes.