Mutual Screw & Supply

5/16-18 X 1-3/8" Hex Machine Bolts | Steel Zinc Plated | Partially Threaded (200 / Pkg.)

5/16-18 X 1-3/8" Hex Machine Bolts | Steel Zinc Plated | Partially Threaded - Main image
$9.12 $14.25 In stock

5/16-18 X 1-3/8" Hex Machine Bolts in Steel Zinc Plated. A hex head machine bolt with a partially threaded shank per ASME B18.2.1, providing an unthreaded grip length for bolted connections through clearance holes.

  • Partially threaded shank for a smooth bearing surface in the shear plane of bolted joints
  • Hex head for wrench-driven, high-torque installation
  • Zinc plating for everyday corrosion resistance

Specifications

  • Type: Hex Machine Bolts
  • Head Style: Hex
  • Material: Steel
  • Finish: Zinc Plated
  • Thread Size: 5/16-18
  • Length: 1-3/8"
  • Thread: Partially Threaded
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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 (4.4 / 5 · 5 reviews)

Jason ★★★★★

Used these on a trailer hitch mount where the unthreaded grip length was exactly what I needed to keep things tight. The zinc coating has held up fine through some wet weather so far.

Sophia S. ★★★★★

I needed some bolts for a machinery repair where the grip length was critical, and these 5/16-18 hex heads fit the unthreaded shank requirement perfectly. The zinc plating seems consistent and corrosion-resistant, though the package of 200 is almost too many for my small workshop.

Emily ★★★★★

These bolts fit perfectly into my frame jig, and the unthreaded grip length made aligning everything much easier. The zinc coating looks clean and adds a nice layer of protection. I'm really happy with the quality for the price.