Mutual Screw & Supply

HOLO-KROME 72142 5/16-18 X 2-3/4" Socket Cap Screws | Hex Socket Drive | Alloy Steel Thermal Black Oxide (100 / Pkg.)

HOLO-KROME 72142 5/16-18 X 2-3/4" Socket Cap Screws | Hex Socket Drive | Alloy - Main image
$40.83 $65.86 In stock

These 5/16-18 x 2-3/4" socket cap screws are manufactured from Alloy Steel Thermal Black Oxide, featuring a socket drive. They are well suited to machinery, tooling, jigs, and precision assemblies.

  • Material and finish: Alloy Steel Thermal Black Oxide
  • Drive: Socket Drive
  • Thread size: 5/16-18
  • Length: 2-3/4"
  • Applications: Machinery, tooling, jigs, and precision assemblies

Specifications

  • Product type: Socket Cap Screws
  • Material: Alloy Steel
  • Finish: Thermal Black Oxide
  • Drive type: Socket Drive
  • Thread size: 5/16-18
  • Length: 2-3/4"
  • Threads per inch: 18
  • Measurement type: Inch
  • Pack quantity: 100 per package
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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)

Ellie F. ★★★★★

Finally a bolt that doesn't strip before reaching full torque—the black oxide finish held up perfectly in my press fixture. Needed a solid 5/16-18 for a custom die mount and these socket caps fit the hole exactly with no slop.

John Y. ★★★★★

Installed these on a jig I’m building for a custom fixture, and the black oxide coating feels like it’ll resist rust well in my shop. The hex drive seated perfectly with no stripping during tightening.

Thomas M. ★★★★☆

Sized up my bench vise rebuild perfectly, and the 2-3/4" length gives just the right grip for the fixture plates I bolt down. The thermal black oxide coating makes them slide in smooth without any binding, though I wish the threads were a touch cleaner out of the pack. Solid for the price, and I’ve