The Yale high security door chain is high quality made from strong and reliable hardened steel. Heavy-duty, surface fitted accessory which is simple to install Helps identify caller before the door is fully released Simple to install; suitable for wooden doors Helps to hold the door in the slightly open position Restrains against a forced attack Easy to use Hardened Steel Suitable for use on internal doors 850-1100 mm wide or external doors 950 mm wide.
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