Mutual Screw & Supply

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

#4-40 X 3" Socket Cap Screws | Hex Socket Drive | Fully Threaded | Alloy Steel - Main image
$174.26 $281.07 In stock

These #4-40 x 3" 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 style: Fully Threaded
  • Thread size: #4-40
  • Length: 3"
  • 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 style: Fully Threaded
  • Thread size: #4-40
  • Length: 3"
  • 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 (4.6 / 5 · 5 reviews)

Victoria ★★★★★

I needed some longer fasteners for a jig I was building, and these #4-40 x 3" socket cap screws fit perfectly. The hex socket drive made them easy to tighten without stripping, and the black oxide seems durable.

Stella R. ★★★★★

Finally got the #4-40s in a 3-inch length for mounting some circuit boards in a tight enclosure. The hex socket drive makes it easy to get good torque even in deep holes. These feel sturdy and the black oxide finish looks clean.

Charlotte H. ★★★★★

Needed some longer 4-40s for a custom jig, and these thermal black oxide screws fit perfectly into the precision assembly. The threads are clean and the hex socket drove smoothly without any cam-out, even at three inches long. A solid pack for the price.