Mutual Screw & Supply

5/16-18 X 1/2" Hex Head Cap Screws | USA Made | Grade L9 Alloy Steel Yellow Zinc | Fully Threaded (100 / Pkg.)

5/16-18 X 1/2" Hex Head Cap Screws | USA Made | Grade L9 Alloy Steel Yellow - Main image
$36.25 $53.31 In stock

5/16-18 x 1/2" hex head cap screws for machinery, equipment assembly and general industrial fastening.

  • Grade L9 Alloy Steel Yellow Zinc construction
  • Fully Threaded
  • Hex head for wrench or socket drive
  • Made in the USA
  • Sold in packs of 100

Specifications

  • Thread Size: 5/16-18
  • Length: 1/2"
  • Threads Per Inch: 18
  • Material: Alloy Steel
  • Grade: Grade L9
  • Finish: Yellow Zinc CR+3
  • Thread Style: Fully Threaded
  • Pack Quantity: 100
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Standard Shipping: Handling (business days) 0–1; Transit (business days) 7–15.

Express Shipping: Handling (business days) 0–1; Transit (business days) 7–15.

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Delivery costs

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Standard Shipping · United States: $0.00

Express Shipping · United States: $3.99

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Returning an item

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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)

Ryan ★★★★★

The yellow zinc finish on these has held up nicely on the equipment I’m assembling, and the L9 alloy steel feels seriously tough for the price. Fully threaded too, so I didn’t have to fiddle with alignment on the bracket. These are going to be my go-to for shop jobs from now on.

Sophia ★★★★★

Needed some serious 5/16-18 bolts for a heavy-duty jig I was building and these L9s are definitely up to the task. The hex heads give a perfect bite with a socket, no rounding at all during torquing.

Sofia H. ★★★★★

The yellow zinc coating on these L9 bolts is holding up great in our shop; I’ve used about half the pack on a jig assembly and every one threaded in cleanly without any binding.