Nuts and washers not included, ensure washers and nuts are same diameter About this item These aren't just any bolts - that smooth rounded head means no scraped knees or torn clothes! The 1/4-20 x 1-1/2 size is perfect for docks, playgrounds, or anywhere you don't want sharp edges. The square shoulder locks it in place while you tighten the nut (sold separately, FYI). Pro tip: Make sure your washers/nuts match the 1/4 diameter. Comes in a bulk 100-pack because... Due to that reason, they are often used when a more aesthetic look is desired. 1/4-20x6-1/2 Carriage Bolt Grade 2 Zinc - MacDonald Industrial Supply Bolt Without Sharp Edges Prime-Line Carriage Bolts 1/4in-20 X 6in A307 Grade A Zinc Plated Steel 50pk 9062661 Dock Hardware Smooth Head Bolts Often used in cases where a protruding bolt head could cause injury MF Supply is a leading supplier of 1/4-20 X 1-1/2 Carriage Bolt Flat Head Low Carbon Steel Zinc Full Thread. Buy online or request a custom quote today Square shoulder allows for nut to be tightened or loosened Diameter-Thread Size & Length: 1/4 inch-20 X 1-1/2 inch