Mutual Screw & Supply

5/16-18 X 1-3/8" Socket Cap Screws | Flat Head Hex Socket Drive | Fully Threaded | Alloy Steel Thermal Black Oxide (100 / Pkg.)

5/16-18 X 1-3/8" Socket Cap Screws | Flat Head Hex Socket Drive | Fully - Main image
$60.32 $83.78 In stock

These 5/16-18 x 1-3/8" 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: Flat Head
  • Drive: Hex Socket Drive
  • Thread style: Fully Threaded
  • Thread size: 5/16-18
  • Length: 1-3/8"
  • 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: Hex Socket Drive
  • Thread style: Fully Threaded
  • Thread size: 5/16-18
  • Length: 1-3/8"
  • 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 (5.0 / 5 · 5 reviews)

Robert ★★★★★

The hex socket drive really grabs onto the driver without slipping, making installation a breeze. I used these for a jig build and the threads cut cleanly into the material. Great value for the pack of 100.

David J. ★★★★★

The black oxide finish on these screws looks clean and professional, and the hex socket drive made installation a breeze with my allen wrench. They threaded smoothly into my jig setup without any binding.

Adam K. ★★★★★

Got my precision assembly table up and running last weekend, and these flat head screws sat perfectly flush in the countersunk holes. The black oxide finish on the alloy steel feels durable and hasn’t chipped during tightening.