Mutual Screw & Supply

HOLO-KROME 60004 #4-40 X 3/8" Socket Cap Screws | Flat Head Hex Socket Drive | Alloy Steel Thermal Black Oxide (100 / Pkg.)

HOLO-KROME 60004 #4-40 X 3/8" Socket Cap Screws | Flat Head Hex Socket Drive | - Main image
$16.41 $25.25 In stock

These #4-40 x 3/8" socket cap screws are manufactured from Alloy Steel Thermal Black Oxide, featuring a 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: Socket Drive
  • Thread size: #4-40
  • Length: 3/8"
  • 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: 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 (4.6 / 5 · 5 reviews)

Sofia R. ★★★★★

Finally, a flat head screw that actually sits flush in my fixture without needing to be counterbored deeper. The black oxide finish matched perfectly on my tooling project and none of the heads stripped out during installation.

Scarlett V. ★★★★★

Picked up these #4-40 x 3/8" screws for a small machine tool rebuild, and the black oxide finish took a wrenching without a single chip. The flat head sits perfectly flush, zero wobble.

Joshua ★★★★★

I needed some small screws for a jig I’m building, and these #4-40 x 3/8" flat heads fit perfectly with no stripping at all. The black oxide finish looks clean and seems durable against light shop wear.