Mutual Screw & Supply

1/4-20 X 3-1/4" Carriage Bolts | Fully Threaded | A307 Grade A Plain Steel (550 / Pkg.)

1/4-20 X 3-1/4" Carriage Bolts | Fully Threaded | A307 Grade A Plain Steel (550 - Main image
$42.87 $60.38 In stock

1/4-20 X 3-1/4" 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: 1/4-20
  • Length: 3-1/4"
  • Threads Per Inch: 20
  • Material: A307 Grade A Plain Steel
  • Finish: Plain
  • Thread Style: Fully Threaded
  • Pack Quantity: 550
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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)

Penelope P. ★★★★★

I used these for a deck repair and the fully threaded shaft made installation much smoother than the partial-thread bolts I’ve fought with before. The 550-count box gives you plenty of spares for future projects, too.

Michael ★★★★★

The square neck on these bolts grabbed perfectly into the wood, so no need for a second wrench to tighten them. For a hardware pack this size, the plain steel finish looks uniform and clean right out of the box.

Avery ★★★★★

Used these for a pergola project and the fully threaded length made installation a breeze. The A307 grade steel feels solid and the square neck grabbed tight into the wood just like it should. Over 500 bolts in the pack was way more than I needed, but the price was right for the quantity.