Mutual Screw & Supply

5/16-18 X 5/8" Socket Cap Screws | Hex Socket Drive | Nylon Pellet | Fully Threaded | Alloy Steel Thermal Black Oxide (100 / Pkg.)

5/16-18 X 5/8" Socket Cap Screws | Hex Socket Drive | Nylon Pellet | Fully - Main image
$153.04 $221.79 In stock

These 5/16-18 x 5/8" 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 style: Fully Threaded
  • Thread size: 5/16-18
  • Length: 5/8"
  • 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 style: Fully Threaded
  • Thread size: 5/16-18
  • Length: 5/8"
  • Threads per inch: 18
  • 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)

Andrew ★★★★★

These screws worked perfectly for a jig I was building — the black oxide coating gives them a nice finished look and seems durable. The hex socket made installation quick with no stripped heads.

Ava ★★★★★

The nylon pellet locking feature is a lifesaver—these screws stay put even on vibrating machinery. The black oxide finish looks good and seems to resist rust so far. Exactly what I needed for my jig setup.

Emily Y. ★★★★★

The hex socket drive on these screws gripped my driver bit perfectly on a jig build, zero stripping or cam-out. The nylon pellet locked the threads down tight, and the black oxide coating slid through the fixture cleanly. Exactly what I needed for precision assembly work.