Mutual Screw & Supply

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

#4-40 X 3/8" Socket Cap Screws | Button Head Hex Socket Drive | Nylon Pellet | - Main image
$44.86 $64.08 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
  • Head style: Button Head
  • Drive: Hex Socket Drive
  • Thread style: Fully Threaded
  • Thread size: #4-40
  • Length: 3/8"
  • Applications: Machinery, tooling, jigs, and precision assemblies

Specifications

  • Product type: Socket Cap Screws
  • Head style: Button Head
  • Material: Alloy Steel
  • Finish: Thermal Black Oxide
  • Drive type: Hex Socket Drive
  • Thread style: Fully Threaded
  • 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 (4.8 / 5 · 5 reviews)

Scarlett Z. ★★★★★

The #4-40 thread cut cleanly with no galling, and the thermal black oxide finish looks properly done for a machine environment. Bag count matched exactly, and the nylon pellet keeps tension where I need it.

George ★★★★★

The hex socket drive on these is perfect for tight spots where a regular screwdriver can't reach, and the nylon pellet holds them snug once torqued down. Just finished a small jig with them and every one of the hundred seated cleanly without a single stripped thread.

Thomas ★★★★★

The black oxide finish on these #4-40 screws gives them a nice, uniform look in my jig setup. They fit perfectly in tight spots with the button head and hex drive, making adjustments quick.