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Zinc-plated steel heavy hex nut, 5/16-18 thread

MIDWEST FASTENER CORP

MIDWEST FASTENER CORP Heavy Hex Nut 5/16"-18 Steel Grade 2 Zinc Plated 03706

SKU CH-C0FQ-E6A6N

Heavy hex nut with 5/16"-18 thread secures bolts and machine screws in steel assemblies

  • TypeNuts
  • Heavy-duty fastening with Grade 2 steel strength
  • Corrosion resistance from zinc-plated finish
  • Fits 5/16"-18 bolts and machine screws
  • Heavy hex design distributes load across wider surface
  • New hardware ready for immediate installation

Heavy Hex Nut 5/16"-18

The MIDWEST FASTENER CORP heavy hex nut fits 5/16"-18 machine screws and bolts. It is made from Grade 2 steel with a zinc plated finish. This fastener suits general purpose assembly and repair tasks. It is supplied new for immediate use.

Grade 2 Steel Zinc Plated

Grade 2 steel provides standard strength for non-critical joints. The zinc plating adds a layer of corrosion resistance for everyday environments. The heavy hex pattern offers a larger bearing surface than standard hex nuts. This helps distribute clamping force across the joint.

Replaces Standard Hex Nuts

Use this nut when a wider bearing face is needed to prevent pull-through on softer materials. It upgrades from standard hex nuts where load distribution matters. The jump is worth it for repair work on slotted or oversized holes. It is not for applications requiring high tensile strength or structural certification.

Highlights

  • Heavy-duty fastening with Grade 2 steel strength
  • Corrosion resistance from zinc-plated finish
  • Fits 5/16"-18 bolts and machine screws
  • Heavy hex design distributes load across wider surface
  • New hardware ready for immediate installation

Specifications

BrandMIDWEST FASTENER
TypeNuts

Questions about this item

What thread pitch does the 5/16"-18 heavy hex nut use?

The nut uses an 18 threads-per-inch pitch, which matches standard coarse-thread bolts in the same diameter.

What wrench size fits the heavy hex nut?

A 1/2-inch wrench or socket is required to engage the heavy hex flats on this 5/16-inch nut.

How is the nut installed onto a bolt?

Thread the nut onto the bolt by hand until snug, then tighten with a 1/2-inch wrench; the common mistake is cross-threading the first few turns.

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