Mutual Screw & Supply

5/16-18 X 5/16" Socket Cap Screws | Hex Socket Drive | USA Made | Fully Threaded | Alloy Steel Thermal Black Oxide (100 / Pkg.)

5/16-18 X 5/16" Socket Cap Screws | Hex Socket Drive | USA Made | Fully - Main image
$671.88 $907.94 In stock

These 5/16-18 x 5/16" socket cap screws are manufactured from Alloy Steel Thermal Black Oxide, featuring a hex socket drive. They are well suited to machinery, tooling, jigs, and precision assemblies.

  • Material and finish: Alloy Steel Thermal Black Oxide
  • Drive: Hex Socket Drive
  • Thread style: Fully Threaded
  • Thread size: 5/16-18
  • Length: 5/16"
  • Applications: Machinery, tooling, jigs, and precision assemblies

Specifications

  • Product type: Socket Cap Screws
  • Material: Alloy Steel
  • Finish: Thermal Black Oxide
  • Drive type: Hex Socket Drive
  • Thread style: Fully Threaded
  • Thread size: 5/16-18
  • Length: 5/16"
  • Threads per inch: 18
  • Measurement type: Inch
  • Pack quantity: 100 per package
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Express Shipping: Handling (business days) 0–1; Transit (business days) 7–15.

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Standard Shipping · United States: $0.00

Express Shipping · United States: $3.99

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United States · Return window (days after delivery): 30. Return method: By mail. Return postage: Seller pays.

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Customer Reviews (4.4 / 5 · 5 reviews)

David F. ★★★★★

I needed some short but strong screws for a jig I was building, and these 5/16-18 socket caps fit perfectly without any stripped threads. The hex drive made installation quick with my Allen wrench, and the USA-made alloy steel feels solid.

Sebastian ★★★★★

The black oxide finish on these screws looks professional and resisted scuffing when I tightened them into a jig. The hex socket drive seated firmly with no stripping, and the fully threaded body gripped the tapped hole perfectly on every one.

George R. ★★★★☆

I needed a handful for a jig I was building, and these hex drive screws fit the bill perfectly. The fully threaded shank grabbed well in the tapped hole, and the black oxide gives them a clean, professional look. No stripped sockets, so I’m happy with the quality for the price.