Mutual Screw & Supply

1/4-20 X 3-1/2" Socket Cap Screws | Flat Head Hex Socket Drive | Partially Threaded | Alloy Steel Thermal Black Oxide (100 / Pkg.)

1/4-20 X 3-1/2" Socket Cap Screws | Flat Head Hex Socket Drive | Partially - Main image
$39.88 $65.38 In stock

These 1/4-20 x 3-1/2" 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: 1/4-20
  • Length: 3-1/2"
  • 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: 1/4-20
  • Length: 3-1/2"
  • Threads per inch: 20
  • 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)

Grace I. ★★★★★

The hex socket drive grabbed firmly with my Allen key, no stripping even when I torqued these down into a steel jig. The black oxide finish looks clean and resisted rust after a few days in a damp shop. Solid buy for precision assemblies.

Matthew B. ★★★★★

The partially threaded design made lining up my jig plates a lot easier, and the black oxide finish looks sharp against the aluminum. They torqued down smoothly without any stripped heads, so I’ve got no complaints for the price.

Lily H. ★★★★★

The hex socket drive on these screws bites cleanly into my driver without any wobble, and the black oxide finish has a nice, even texture that feels solid in hand. I used them to build a small fixture for my drill press and the 3-1/2" length with the partial threading gave me just the right amount o