Size:M3/M4/M5/M6/M8/M10/M12. Over-tightening may strip threads. ✓Fast Installation : Square shape allows wrench/piping pliers grip, 50% faster tightening. Material: A2 Stainless Steel. Grade 304 Stainless Steel : 18% chromium & 8% nickel (ASTM A276 certified), excels in corrosion resistance (500+ hours salt spray test).
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