Mutual Screw & Supply

5/16-18 X 4" Socket Cap Screws | Flat Head Hex Socket Drive | Partially Threaded | Alloy Steel Thermal Black Oxide (100 / Pkg.)

5/16-18 X 4" Socket Cap Screws | Flat Head Hex Socket Drive | Partially - Main image
$62.54 $102.52 In stock

These 5/16-18 x 4" 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: 4"
  • 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: 4"
  • 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 (4.4 / 5 · 5 reviews)

Nicholas ★★★★★

Installed these on a custom jig I'm building and the flat head hex socket fits perfectly flush. The thermal black oxide finish has a nice, uniform look and seems tougher than cheap zinc-plated bolts.

Ryan T. ★★★★★

The partially threaded design was perfect for my jig setup, and the black oxide finish held up nicely against shop grime. The hex socket drive seated cleanly in my drivers without any stripping, and the alloy steel feels solid at this price point.

Carter Q. ★★★★☆

The partially threaded design made alignment much easier when fastening a steel bracket to a thick wooden workbench. The black oxide finish looks clean and has held up well under light shop use so far. Only wish they came with a few extra washers in the pack.