Mutual Screw & Supply

5/16-18 X 3" Carriage Bolts | Fully Threaded | 316 Stainless Steel (100 / Pkg.)

5/16-18 X 3" Carriage Bolts | Fully Threaded | 316 Stainless Steel (100 / Pkg.) - Main image
$32.26 $52.03 In stock

5/16-18 X 3" Carriage Bolts in 316 Stainless 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
  • 316 Stainless 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: 316 Stainless Steel
  • Finish: Plain
  • Thread Style: Fully Threaded
  • Pack Quantity: 100
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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 (4.8 / 5 · 5 reviews)

Stella T. ★★★★★

Installed these on a new gate hinge and the square neck grabbed perfectly, no spinning. The 316 stainless feels seriously heavy-duty compared to standard hardware.

Ava N. ★★★★★

Used these for a dock repair and the square neck really grabbed into the wood—no spinning at all. The 316 stainless is holding up great in saltwater. Exactly what I needed.

Scarlett ★★★★★

Installed these on new deck framing and they pulled the wood tight without spinning once—just like they should. The fully threaded shaft made it easy to get full bite into the pressure-treated lumber.