Mutual Screw & Supply

5/16-18 X 1/2" Carriage Bolts | Fully Threaded | A307 Grade A Plain Steel (300 / Pkg.)

5/16-18 X 1/2" Carriage Bolts | Fully Threaded | A307 Grade A Plain Steel (300 - Main image
$10.94 $17.94 In stock

5/16-18 X 1/2" 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: 1/2"
  • Threads Per Inch: 18
  • Material: A307 Grade A Plain Steel
  • Finish: Plain
  • Thread Style: Fully Threaded
  • Pack Quantity: 100
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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 (5.0 / 5 · 5 reviews)

Henry ★★★★★

Used these for a shed build and the smooth rounded heads gave it a clean finish. The square neck locked right into the wood, no spinning at all. A full box of 300 was plenty, and the price per bolt felt fair for the quantity.

Robert W. ★★★★★

The square neck under the head grabbed tight on the first pull, no spinning or cursing on this job. For 300 bolts in plain steel at this price, they’re a solid buy.

Hazel ★★★★★

I needed a bunch of carriage bolts for a project and the square neck under the head really did its job, gripping into the wood so the bolt stayed put while I tightened the nut. A full 300 in the pack meant I didn’t have to stop and order more halfway through.