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HILLMAN 5/16 in. Zinc-Plated Steel SAE Acorn Nut

HILLMAN 5/16 in. Zinc-Plated Steel SAE Acorn Nut

Elevate your hardware projects with the Hillman 5/16 in. Zinc-Plated Steel SAE Acorn Nut. This 100-piece boxed set combines a clean, finished look with dependable protection for bo…

Hillman MPN 180090 In Stock & Ready to Ship
Local Price Check i Local stores may price this as low as $31.99. Our online price is $35.99.
$35.99
Includes free shipping on orders over $75 · $8.99 standard below
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You might find it for less locally. Independent retailers often offer competitive pricing — some products are even cheaper in-store than online.
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About Product Overview

Elevate your hardware projects with the Hillman 5/16 in. Zinc-Plated Steel SAE Acorn Nut. This 100-piece boxed set combines a clean, finished look with dependable protection for bolt ends, making it ideal for both indoor installations and outdoor applications where corrosion resistance is a must.

  • Size and threading: 5/16" diameter with a coarse-thread profile to pair with standard bolts and provide quick, confident installation.
  • Material and finish: Durable steel construction coated with zinc plating to resist rust and wear in challenging environments.
  • Acorn nut design: Closed-end cap covers the bolt tip for a neat appearance, plus added safety by preventing snagging or exposed threads.
  • Packaging: A boxed set of 100 pieces, organized for easy storage and fast-access during large or ongoing projects.
  • Compatibility: SAE unit, designed to work with common hardware in woodworking, metalworking, outdoor furniture, automotive projects, and more.

Why this matters: The zinc-plated steel combines strength with long-lasting protection against corrosion, so bolt ends stay concealed and look professional even in damp or outdoor settings. The acorn shape creates a smooth, finished silhouette on furniture, decking, gates, fencing, machinery, and equipment enclosures, reducing snag hazards and improving safety for families and workers alike.

Ideal use cases:

  • Outdoor decks, railing systems, and gates where end caps prevent moisture ingress and provide a polished look.
  • Woodworking and furniture projects requiring a clean, discontinued bolt tip.
  • Automotive, bicycle racks, and garden equipment where durable protection is key to longevity.
  • Repairs and replacements in shops or garages where a reliable, bulk supply is beneficial.

Installation tips: Align the acorn nut with the bolt, thread it on by hand to ensure proper engagement, then tighten with the appropriate wrench or socket until the cap sits flush. For outdoor projects, store in a dry place to maximize the finish and extend life between uses.

Choose Hillman for dependable hardware solutions that combine practical function with a polished appearance. This 5/16" zinc-plated steel acorn nut set delivers consistent threads, a protective finish, and a tidy, finished aesthetic across a wide range of projects.

The Details Specifications

Brand Hillman
SKU 51980
UPC 008236072716
Unit 0
Case Pack Quantity 9 per case
Retail Unit Quantity 1
Unit of Measure 100 BX
Dimensions (L × W × H) 3 × 3 × 2
Weight 2 lbs
Cubic Feet 0.02258 ft³
Country of Origin TAIWAN
Safety Data Sheet (SDS) Manufacturer documentation · opens in new tab

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The stores we send you to are local and independently run — often for generations, the kind of place where someone behind the counter knows the regulars. We don't own them. We just think they deserve the foot traffic. They can put most of what we sell on their next truck. Ask there before you check out here.

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About our directory. National Hardware Group is an independent retailer and directory. The local stores we list and link to are separately owned and operated — we have no ownership stake in any of them, and most pay us nothing to be included. That includes plenty of stores flying a co-op banner that people don't realize are locally owned and run, not operated by a corporation. Store owners can choose to upgrade their listing for an enhanced presence or pickup features, but the base directory is free, and inclusion is never a paid endorsement.

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