5/8" x 7" UNC Hex Bolt, 316 Stainless Steel - XHBA458UNCX7

The UNC Hex Bolt, 316 Stainless Steel is a hex head bolt tightened with a spanner or socket. Unlike a hex set bolt, which is threaded full length, a hex bolt is partly threaded with a plain shank under the head, so the thread length is set by the bolt length.

This listing has 96 variants covering sizes 1/4" to 1" and lengths 1-1/4" to 8". Pack quantities depend on size: packs of 10 to 100.

Supplied in 316 (A4) stainless steel. The molybdenum in A4 gives better resistance to chlorides than A2 (304), so it is the usual choice near the coast, around pools and in marine and food-processing environments. UNC (Unified National Coarse) is the coarse inch-based thread. Small sizes are given as a number and threads per inch, such as 8-32 or 10-24, and larger sizes as fractions of an inch.

Austenitic stainless steel is generally non-magnetic, although cold-worked parts can show weak magnetism. Stainless threads can gall (seize) when tightened under load or at speed. A smear of anti-seize on the thread and a steady tightening speed reduce the risk.

Where this product is used

• Structural and machinery connections tightened with a spanner or socket
• Outdoor fittings exposed to salt air
• Larger sizes for frames, plant and structural fixings
• Replacement fasteners for imported, inch-sized equipment
• Marine, coastal and washdown fabrications
• Outdoor furniture, playground and architectural metalwork

Features

• Pack quantities to suit trade and bulk buying: packs of 10 to 100
• A4 (316) stainless steel with molybdenum, for coastal and chloride-exposed settings
• Plain shank under the head for shear loads
• Hex head for spanner or socket tightening
• Inch sizing matches imported UNC equipment
• Range covers 1/4" to 1" in 96 variants

Key specifications

Selecting the right option

Choose a length that leaves at least one full thread showing past the nut and keeps the thread out of the shear plane where the joint is loaded sideways. Use a stainless flat washer under the head and the nut, and anti-seize on the thread, because stainless threads can gall when tightened. Where chlorides are not a concern, the A2 (304) version costs less: UNC Hex Bolt - 304 Stainless Steel.

Related products

Other versions in this range: Metric Hex Bolt - 304 Stainless Steel and Metric Hex Bolt - 316 Stainless Steel. Often used with: UNC Standard Hex Nut - 316 Stainless Steel, UNC Hex Lock Nut - 316 Stainless Steel and UNC Hex Nylon Insert Lock Nut - 316 Stainless Steel.