Mutual Screw & Supply

5/16-18 X 3/4" Carriage Bolts | Fully Threaded | A307 Grade A Zinc Plated Steel (375 / Pkg.)

5/16-18 X 3/4" Carriage Bolts | Fully Threaded | A307 Grade A Zinc Plated Steel - Main image
$13.48 $19.83 In stock

5/16-18 X 3/4" 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
  • Fully Threaded
  • Sold in bulk packs

Specifications

  • Thread Size: 5/16-18
  • Length: 3/4"
  • Threads Per Inch: 18
  • Material: A307 Grade A Zinc Plated Steel
  • Finish: Zinc Plated
  • Thread Style: Fully Threaded
  • Pack Quantity: 125
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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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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)

Lily R. ★★★★★

The square neck under the head grabbed the wood immediately, so I didn't have to wrestle a wrench to keep them from spinning. For 375 pieces at this price, the zinc coating looks even and clean across the whole batch.

Chloe E. ★★★★★

Used these to secure some pergola brackets to a treated lumber beam; the square neck grabbed perfectly and kept them from spinning while I tightened everything down. The zinc plating gives them a nice, clean finish that should hold up well outdoors.

Ava W. ★★★★★

Installed a bunch of these on a wooden gate yesterday and that square neck under the head really locks them in place—no spinning while tightening. The zinc coating is consistent and smooth, and the whole pack had clean threads.