Mutual Screw & Supply

#4-40 X 3/8" Socket Cap Screws | Low Head Hex Socket Drive | Alloy Steel Thermal Black Oxide (100 / Pkg.)

#4-40 X 3/8" Socket Cap Screws | Low Head Hex Socket Drive | Alloy Steel - Main image
$42.31 $56.41 In stock

These #4-40 x 3/8" 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: #4-40
  • Length: 3/8"
  • 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: #4-40
  • Length: 3/8"
  • Threads per inch: 40
  • 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 (5.0 / 5 · 5 reviews)

Miles T. ★★★★★

The black oxide finish on these screws gives them a really solid, professional look for small tooling projects. I used them on a precision assembly and the hex socket drive bit held perfectly without any stripping, even at low torque. They fit exactly as expected for a #4-40, which is always reassur

Madison ★★★★★

These #4-40s are perfect for the jig I'm building, the black oxide finish is a nice touch. They thread smoothly into tapped holes without binding.

Steven ★★★★★

The hex socket drive makes these tiny screws super easy to tighten without stripping, and the black oxide coating gives them a nice, uniform look for my jig assembly.