Heavy Hex Nuts
A heavy hex nut is a larger, thicker pattern than a standard (finished) hex nut of the same thread size — wider across the flats and taller, giving more bearing surface and thread engagement. That extra material makes it the choice for larger-diameter bolting and higher-load joints in equipment, machinery, and construction. Eugene Fastener & Supply stocks heavy hex nuts in Grade 2, Grade 5, and 18-8 stainless, inch and metric, in coarse and fine threads.
For A325/A490 structural-steel connections specifically, use our structural heavy hex nuts (A194 2H and A563 DH). Match the heavy hex nut grade to your bolt so the nut is never the weak link. We sell by the piece or in bulk, cross-reference part numbers, and ship same day on orders placed before 2pm Pacific.
Goes Well With
Heavy Hex Nuts — Grade 2, 5 & Stainless
Need heavy hex nuts for a production run or a specific grade?
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Heavy Hex Nuts by Grade & Material
- Grade 2 Heavy Hex Nuts — general-purpose, larger pattern.
- Grade 5 Heavy Hex Nuts — medium-strength for higher-load joints.
- Stainless Heavy Hex Nuts — 18-8 corrosion resistance.
For A325/A490 structural connections, see our structural heavy hex nuts (A194 2H & A563 DH).
Heavy Hex vs. Finished Hex Nut
A heavy hex nut is wider across the flats and taller than a standard finished hex nut of the same thread, so it has more bearing area and thread engagement and carries more load. Use finished hex for general bolting; step up to heavy hex for larger diameters, higher loads, and structural or equipment joints — and to structural heavy hex (A194/A563) when a code or spec calls it out.
Heavy Hex Nut FAQ
What is a heavy hex nut?
A heavy hex nut is a larger, thicker pattern than a standard finished hex nut of the same thread size — wider across the flats and taller. The extra material gives more bearing surface and thread engagement, so it carries higher load. It’s used on larger-diameter bolting and in equipment, machinery, and construction.
What’s the difference between a heavy hex nut and a finished hex nut?
Same thread, bigger nut. A heavy hex is wider across the flats and taller than a finished hex of the same diameter, giving more bearing area and strength. Use finished hex for general work and heavy hex for larger sizes, higher loads, and structural or equipment joints.
When do I need a structural heavy hex nut instead?
When the joint uses A325 or A490 structural bolts, or a spec calls out A194 2H or A563 DH. Those are graded for structural-steel and high-temperature/pressure service. See our structural heavy hex nuts for those callouts.
What grades and materials are available?
Grade 2 and Grade 5 steel and 18-8 stainless, inch and metric, in coarse and fine threads. Match the nut grade to your bolt.
Do you stock metric heavy hex nuts?
Yes, in coarse and fine pitch. If a size isn’t shown online, contact us and we’ll source it.
Do you sell by the piece and cross-reference part numbers?
Both by the piece and in bulk. Send any manufacturer or DIN part number and we’ll match it, usually same business day.
Why Buy Heavy Hex Nuts from Eugene Fastener
- Grade 2, Grade 5, and stainless, inch and metric.
- Structural grades too (A194 2H, A563 DH) for A325/A490 joints.
- By the piece or in bulk, with cross-reference and grade matching.
- Since 1969 — serving Pacific Northwest industry for over 55 years.
Match heavy hex nuts with our bolts and cap screws and washers. For structural steel, see structural heavy hex nuts; for general work, finished hex nuts. Browse all nut types or contact our sales team. Eugene Fastener & Supply — serving the Pacific Northwest since 1969.