Mutual Screw & Supply

7/8-9 X 3-1/4" Socket Cap Screws | Hex Socket Drive | USA Made | Alloy Steel Thermal Black Oxide (10 / Pkg.)

7/8-9 X 3-1/4" Socket Cap Screws | Hex Socket Drive | USA Made | Alloy Steel - Main image
$52.28 $87.13 In stock

These 7/8-9 x 3-1/4" 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
  • Drive: Hex Socket Drive
  • Thread size: 7/8-9
  • Length: 3-1/4"
  • 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 size: 7/8-9
  • Length: 3-1/4"
  • Threads per inch: 9
  • Measurement type: Inch
  • Pack quantity: 10 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 (4.6 / 5 · 5 reviews)

Miles ★★★★★

Installed these on a heavy-duty jig I’m building—the hex socket drive fit my allen wrench perfectly, and the USA-made alloy steel feels solid. No stripping or wobble when torqued down.

Benjamin F. ★★★★★

The black oxide finish on these screws gives them a nice, uniform look, and the hex socket drive made tightening them into my jig a breeze. They seated firmly without any stripping, exactly what I needed for a heavy-duty assembly.

David Q. ★★★★★

I needed a handful of strong bolts for a jig rebuild, and these 7/8-9 x 3-1/4" socket cap screws fit perfectly. The hex socket drive made installation straightforward, and the thermal black oxide finish seems durable.