Mutual Screw & Supply

3/8-16 X 5-1/2" Socket Cap Screws | Flat Head Hex Socket Drive | Partially Threaded | Alloy Steel Thermal Black Oxide (50 / Pkg.)

3/8-16 X 5-1/2" Socket Cap Screws | Flat Head Hex Socket Drive | Partially - Main image
$84.78 $113.04 In stock

These 3/8-16 x 5-1/2" 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: 3/8-16
  • Length: 5-1/2"
  • 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: 3/8-16
  • Length: 5-1/2"
  • Threads per inch: 16
  • Measurement type: Inch
  • Pack quantity: 50 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)

Sebastian ★★★★★

I used a few of these to secure a jig table top, and the flat head sat perfectly flush in the counterbore. The black oxide finish seems durable and hasn't shown any wear after repeated adjustments.

Adam ★★★★★

I needed longer cap screws for a rig I'm building and the 5-1/2" length with the partial threading worked perfectly for the deep clamping setup. The black oxide finish feels tough and the hex drive seated nicely without stripping.

Riley G. ★★★★★

Installed these on a custom jig and the partially threaded section gave plenty of grip without needing a spacer. The thermal black oxide finish held up nicely through a few test runs.