Size:M4 M5 M6 M8 M10 M12 M14~M20. Nylon Insert Hex Locking Nuts. 304 stainless steel has higher corrosion resistance than 201, higher surface brightness, and is widely used. 304 and 316 are both stainless and acid resistant steel, and both are sanitary grade stainless steel, suitable for use in coastal areas.
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