Mutual Screw & Supply

3/8-16 X 3-1/2" Carriage Bolts | Fully Threaded | A307 Grade A Plain Steel (350 / Pkg.)

3/8-16 X 3-1/2" Carriage Bolts | Fully Threaded | A307 Grade A Plain Steel (350 - Main image
$63.2 $91.59 In stock

3/8-16 X 3-1/2" 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: 3/8-16
  • Length: 3-1/2"
  • Threads Per Inch: 16
  • Material: A307 Grade A Plain Steel
  • Finish: Plain
  • Thread Style: Fully Threaded
  • Pack Quantity: 350
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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)

Madison R. ★★★★★

These bolts threaded smoothly through the pre-drilled holes in my treated lumber. The rounded heads sit flush and look clean. A full 350-count package is great for larger projects.

Riley V. ★★★★★

The square neck grabbed perfectly into the wood, and every bolt seated flush without spinning during assembly. Needed exactly this many for the whole job, too.

George ★★★★★

Bought these for a pergola tie-down and the 3-1/2" length is perfect for sandwiching two 2x4s with a nut to spare. Fully threaded means no wasted cutting time, and the plain steel finish is what I expected for indoor framing work.