UPVC Door Lock Gearbox Fixing Screws Torx T20 M4.0 Grub Screws Mixed Pack Of 10 8 x M4 by 10mm 2 x M4 by 7mm Replacement Screws for uPVC MPL gearboxes. On most gearboxes, top and bottom Screws are 10 mm, and the middle is 7mm i.e. Lockmaster, Safeware etc.
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