M6 Roofing Bolts & Square Nuts. M4, M5, M6, M8mm. M4,M5,M6,M8 A2 Stainless Steel. M3, M4, M5, M6, M8. Each bolt is supplied with one square nut. M5,M6,M8,M10 A2. Manufactured from zinc plated steel.
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