Carriage Bolts Carriage bolts have a shallow, dome-shaped head with a square neck directly underneath. The square neck section is the same size as the diameter of the bolt shank and makes the bolt self-locking when placed through a square hole in metal or when hammered into a round hole in most wood. This allows the fastener to be installed with only a single wrench, working from one side. They are generally used in applications involving metal to wood construction, which applies to most docks and decks. One flat washer and one hex nut of the same size and finish are typically needed for use with each hex bolt (sold separately). Our inventory of carriage bolts includes a variety of lengths and diameters, many of which are available in either stainless steel or hot dipped galvanized finish. If you don't see the size, grade, or finish you are looking for, please call us at 1.800.677.4710. Product Highlights: 1/2" x 4-1/2" carriage bolt Hot dipped galvanized Thread length: 4" Package quantity: 1 piece
