The KFV 2 Rollers & Attachments For Shootbolts 35mm is a 2 roller split spindle lock with serrations for attaching shootbolts at the top and bottom of the door. The hole in the side of case adjacent to the latch contains a small screw. Depending on which side the function is set, turn the screw clockwise or anti clockwise until it stops to reverse the nightlatch function.
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