M7 (7mm) Rectangular 12.2mm 1.6mm. M20 (20mm) Rectangular 33.5mm 4mm. M2 (2mm) Rectangular 4mm 0.6mm. Zinc Plated Steel. Square Section & Rectangular section. M3 (3mm) SQUARE 5.5mm 1mm. M4 (4mm) SQUARE 6.95mm 1.2mm.
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