5/16-18 Galvanized Carriage Bolts
Carriage bolts were originally designed to attach the wheels to the axles of carriages during the 17th and 18th centuries. The best way to install a carriage bolt is to insert it into the pre-drilled hole and tap the bolt so the head is flush with the surface. Fasten with a flat washer, a lock washer, and a nut. The lock washer stops the bolt from loosening, but you can also add an additional nut and tighten the two nuts together.
Carriage bolts are designed for through-bolting where the bolt's square neck is used to keep the bolt from turning as a nut is tightened on the other end. Using a carriage bolt will really clean up the appearance of your outdoor projects-like deck furniture, decks and docks. Available in Hot-Dipped Galvanized for corrosion resistance.