Mutual Screw & Supply

5/16-18 X 3" Socket Cap Screws | Flat Head Hex Socket Drive | Partially Threaded | Alloy Steel Thermal Black Oxide (100 / Pkg.)

5/16-18 X 3" Socket Cap Screws | Flat Head Hex Socket Drive | Partially - Main image
$47.05 $73.52 In stock

These 5/16-18 x 3" 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
  • Head style: Flat Head
  • Drive: Hex Socket Drive
  • Thread style: Partially Threaded
  • Thread size: 5/16-18
  • Length: 3"
  • Applications: Machinery, tooling, jigs, and precision assemblies

Specifications

  • Product type: Socket Cap Screws
  • Head style: Flat Head
  • Material: Alloy Steel
  • Finish: Thermal Black Oxide
  • Drive type: Hex Socket Drive
  • Thread style: Partially Threaded
  • Thread size: 5/16-18
  • Length: 3"
  • Threads per inch: 18
  • Measurement type: Inch
  • Pack quantity: 100 per package
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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 (4.8 / 5 · 5 reviews)

Olivia ★★★★★

I was a bit worried about the partially threaded design, but these screws held perfectly in a heavy jig I built last weekend. The black oxide finish looks clean and seems tough.

Christopher ★★★★★

The hex socket drive seated perfectly on my torque wrench, and the black oxide finish looks great against the steel frame of my repair fixture. Used a dozen of them for a press tool assembly, and the partial threading held firm under load. Exactly the quality I needed for shop fixtures.

Jacob ★★★★★

Bought these for a jig I'm building and the partial threading is perfect for clamping without bottoming out. The hex socket seated cleanly in my driver, no wobble, and the thermal black oxide looks sharp. Solid pack for the price.