BZP Grade Steel Nyloc Nuts. M4 x 0.70mm pitch; 7mm spanner size. Hexagon nyloc nuts with a self locking nylon insert. M3 x 0.50mm pitch; 5.5mm spanner size. M5 x 0.80mm pitch; 8mm spanner size. M6 x 1.00mm pitch; 10mm spanner size.
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