1/2 in. x 3 in. Stainless Steel Carriage Bolt

The 1/2 in. x 3 in. Stainless Steel Carriage Bolt has a square shoulder under a rounded head. The square head resists turning when the nut is tightened or removed. They are good for wood-to-wood connections when the head may not be accessible for tightening. Used in the construction of docks, swing sets, and decks. 13-thread count bolt. Used with overhead wood beams.

What is a carriage bolt?

A form of bolt used to fasten metal to metal or metal to wood. Also called coach bolt and round-head square-neck bolt. The design prevents the bolt from unlocking from the insecure side.

Distinguished from other bolts by its shallow mushroom head. The fact that the cross-section of the shank is square immediately beneath the head. This makes the bolt self-locking when it is placed through a square hole. Install with only one tool.  The shank has no threads, and its diameter equals the side of the square cross-section.

Devised for use through an iron strengthening plate on either side of a wooden beam. The squared part of the bolt fitting into a square hole in the ironwork. It is common to use a carriage bolt to bare timber. The square section giving enough grip to prevent rotation.