Mutual Screw & Supply

HOLO-KROME 78012 #4-40 X 3/8" Socket Cap Screws | Hex Socket Drive | 18/8 Stainless Steel (100 / Pkg.)

HOLO-KROME 78012 #4-40 X 3/8" Socket Cap Screws | Hex Socket Drive | 18/8 - Main image
$28.82 $43.67 In stock

These #4-40 x 3/8" socket cap screws are manufactured from 18/8 Stainless Steel, featuring a socket drive. They are well suited to machinery, tooling, jigs, and precision assemblies.

  • Material and finish: 18/8 Stainless Steel
  • Drive: Socket Drive
  • Thread size: #4-40
  • Length: 3/8"
  • Applications: Machinery, tooling, jigs, and precision assemblies

Specifications

  • Product type: Socket Cap Screws
  • Material: 18/8 Stainless Steel
  • Finish: Plain
  • Grade: 18/8
  • 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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Express Shipping: Handling (business days) 0–1; Transit (business days) 7–15.

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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)

Sebastian ★★★★★

I needed these for a small jig I was building, and the hex socket drive made installation a breeze with my T-handle wrench. The 18/8 stainless steel feels solid and corrosion-resistant, perfect for precision assemblies.

Isabella U. ★★★★★

Finally, a batch of #4-40 screws that actually holds torque without stripping—the hex socket drive makes a huge difference when tightening inside a tight fixture. These 18/8 stainless ones are definitely tougher than the cheap zinc-plated stuff I've been fighting with.

Ellie J. ★★★★★

Used these in a small robotics jig I was building, and the hex socket drove cleanly without stripping. The 18/8 stainless finish gives them a nice, uniform look compared to cheaper zinc-plated ones I've used before.