5 & ASTM A307A Due to that reason, they are often used when a more aesthetic look is desired. Carriage Bolts 5/16in-18 X 1-1/2in A307 Grade A Zinc Plated Steel 50PK Carriage bolts feature a slightly rounded head and have no exposed sharp edges when fully fastened.Size: 5/16 inch-18 X 1-1/2 inchFeatures a smooth rounded head as opposed to a standard hex headSquare shoulder allows for nut to be tightened or loosened Often used in cases where a protruding bolt head could cause injuryNuts and washers not included, ensure washers and nuts are same diameterThread Type: Coarse, Thread Class: UNC-2A, Point Style: BluntSpecification(s) Met: ASME B18..
Carriage Bolts 5/16in-18 X 1-1/2in A307 Grade A Zinc Plated Steel 50PK Carriage bolts feature a slightly rounded head and have no exposed sharp edges when fully fastened. The square shoulder on carriage bolts help to hold it in place while the nut is fastened..