Stainless steel fasteners are ordered in both metric and inch sizes, depending on the equipment standard, project market, and mating parts. For buyers, the main risk is not choosing stainless steel itself. The risk is ordering the wrong diameter, pitch, length, or thread system.

A fastener may look close by eye, but metric and inch threads are not interchangeable. Size confirmation should always come before price comparison.

Metric Stainless Steel Fastener Sizes

Common Metric Size Format

Metric fasteners are described in millimeters. A typical bolt size such as M10 × 40 means a 10 mm nominal thread diameter and 40 mm length. If pitch is important, it should be written clearly, such as M10 × 1.5 × 40.

Metric stainless steel fasteners are common in European, Asian, and global machinery projects. Buyers can review attaches en acier inoxydable when comparing material grades.

Inch Stainless Steel Fastener Sizes

Filetages UNC et UNF

Inch fasteners use fractional diameters and threads per inch. For example, 1/2”-13 UNC × 2” means a 1/2 inch diameter, 13 threads per inch, and 2 inch length.

Inch stainless steel fasteners are common in U.S. machinery, maintenance, marine equipment, and replacement projects.

Size Matching Rules for Buyers

Confirm the Mating Part

A stainless steel bolt must match the nut, tapped hole, washer, or assembly component. Do not convert metric to inch by approximate diameter only.

Check these items before ordering:

• Système métrique ou inch
• Fil grossier ou fin
• Pas ou TPI
• Longueur totale
• Longueur du fil
• Head type or drive type
• Material grade, such as 304 or 316
• Required standard, such as DIN, ISO, ASTM, or ASME

For standard items, buyers can compare attaches standards et le plein produits de fixation gamme.

When Custom Sizes Are Needed

Custom stainless steel fasteners may be required for special thread length, non-standard head shape, shoulder diameter, fine pitch, or drawing-based equipment parts. In these cases, use fixations non standard sur mesure and provide drawings or measured samples.

Conseil final

For stainless steel fastener sizes, accuracy matters more than appearance. Define the thread system, pitch, length, material grade, and standard before ordering. A clear RFQ prevents wrong-thread delivery, assembly failure, and unnecessary replacement cost.