Mutual Screw & Supply

5/16-18 X 6-1/2" Carriage Bolts | A307 Grade A Zinc Plated Steel (50 / Pkg.)

5/16-18 X 6-1/2" Carriage Bolts | A307 Grade A Zinc Plated Steel (50 / Pkg.) - Main image
$14.24 $21.9 In stock

5/16-18 X 6-1/2" Carriage Bolts in A307 Grade A Zinc Plated Steel. Carriage bolts feature a smooth, rounded head with a square neck underneath that pulls into the material to prevent the bolt from turning during installation, making them ideal for wood-to-wood and wood-to-metal connections.

  • Domed head with square anti-rotation neck
  • A307 Grade A Zinc Plated Steel construction
  • Coarse thread for use in wood and with nuts and washers
  • Sold in bulk packs

Specifications

  • Thread Size: 5/16-18
  • Length: 6-1/2"
  • Threads Per Inch: 18
  • Material: A307 Grade A Zinc Plated Steel
  • Finish: Zinc Plated
  • Pack Quantity: 25
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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)

Aurora ★★★★★

The square neck on these grabs the wood instantly and doesn't spin when I tighten the nut. I just finished setting up a pergola and all 50 bolts seated flush without any stripping.

Ella R. ★★★★★

These bolts were exactly what I needed for a heavy-duty timber bench I’m building. The zinc coating looks clean and even, and the rounded head sits flush without snagging. They drove in nice and straight with no bending.

Natalie U. ★★★★★

The square neck grabbed the wood instantly when I tightened them, no spinning or gouging the surface like regular bolts do. Zinc plating is smooth and consistent across all fifty pieces, and every thread was clean right out of the package.