Mutual Screw & Supply

5/16-18 X 3" Carriage Bolts | Fully Threaded | A307 Grade A Plain Steel (625 / Pkg.)

5/16-18 X 3" Carriage Bolts | Fully Threaded | A307 Grade A Plain Steel (625 / - Main image
$79.55 $116.99 In stock

5/16-18 X 3" Carriage Bolts in A307 Grade A Plain 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 Plain 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"
  • Threads Per Inch: 18
  • Material: A307 Grade A Plain Steel
  • Finish: Plain
  • Thread Style: Fully Threaded
  • Pack Quantity: 625
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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)

Stella ★★★★★

Had to replace the deck railing bolts on my old shed, and these carriage bolts were exactly the right length and thread for the job. The square neck under the head locked into the wood perfectly without spinning.

Daniel V. ★★★★★

The square neck grabbed perfectly in the wood on my deck repairs, and all 625 bolts had clean threads right out of the box. They’re exactly the right size for the carriage bolts I needed.

Benjamin ★★★★☆

The price per bolt here is hard to beat for the quantity, and the plain steel finish is exactly what I expected for outdoor framing projects. They're fully threaded, which made cutting some of them down to size a breeze. Only knock is the box they came in was a bit beat up, but the bolts themselves