This is a Knight Fire & Security F10A heavy-duty roller shutter contact with armored cable sleeving. Security Rating: This contact meets Grade 2 Class III standards for commercial burglar alarm systems. Operating Distance: It features an operating gap of approximately 50mm, designed for use on garage or roller shutter doors. Construction: The unit is constructed from robust aluminium and includes 500mm of armoured cable protection. Wiring: It is a 4-wire contact comprising 2 wires for the alarm circuit and 2 wires for tamper protection.
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