Mutual Screw & Supply

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

3/8-16 X 3-1/2" Socket Cap Screws | Flat Head Hex Socket Drive | Fully Threaded - Main image
$28.78 $44.27 In stock

These 3/8-16 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: Fully Threaded
  • Thread size: 3/8-16
  • 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: Fully Threaded
  • Thread size: 3/8-16
  • Length: 3-1/2"
  • 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 (5.0 / 5 · 5 reviews)

Kevin Z. ★★★★★

The black oxide finish on these is exactly what I needed for a production jig build—no glare under shop lights and they threaded into tapped holes cleanly. The flat head sits flush without extra sanding, which saved me time on alignment. Solid buy for tooling work.

Zoe O. ★★★★★

Finally got these for a precision fixture I'm building, and the flat head sits perfectly flush in the countersunk hole. The black oxide finish looks great and seems to resist oil and grime well.

Elizabeth ★★★★★

I needed longer screws for a jig I was building, and these 3-1/2" socket caps fit perfectly. The hex drive seated deep without stripping, and the black oxide coating feels tough and uniform.