Mutual Screw & Supply

3/8-16 X 3-1/4" Hex Head Cap Screws | USA Made | Grade L9 Alloy Steel Yellow Zinc | Partially Threaded (400 / Pkg.)

3/8-16 X 3-1/4" Hex Head Cap Screws | USA Made | Grade L9 Alloy Steel Yellow - Main image
$590.32 $908.19 In stock

3/8-16 x 3-1/4" hex head cap screws for machinery, equipment assembly and general industrial fastening.

  • Grade L9 Alloy Steel Yellow Zinc construction
  • Partially Threaded
  • Hex head for wrench or socket drive
  • Made in the USA
  • Sold in packs of 400

Specifications

  • Thread Size: 3/8-16
  • Length: 3-1/4"
  • Threads Per Inch: 16
  • Material: Alloy Steel
  • Grade: Grade L9
  • Finish: Yellow Zinc CR+3
  • Thread Style: Partially Threaded
  • Pack Quantity: 400
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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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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 (4.8 / 5 · 5 reviews)

Jacob H. ★★★★★

The partial threads are exactly where they should be, so seating these into my equipment frame took no extra fuss. The yellow zinc finish is even and the hex heads grab a socket cleanly. These are going to last through plenty of rebuilds.

Timothy S. ★★★★★

These bolts came with a clean, uniform yellow zinc finish that really resists corrosion on my outdoor equipment. The L9 alloy steel is noticeably tougher than standard hardware I've used before.

Amelia ★★★★★

I needed high-strength bolts for a repair on a press, and these L9 grade screws torqued down perfectly without any galling. The yellow zinc finish looks good on the exposed heads, too.