CARRIAGE BOLTS SCREWS A307 GRADE A, ZINC PLATED
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Carriage Bolts A307 Grade A Zinc Plated are bolts a/k/a screws that have a round smooth head and square neck under the head. Zinc plated A307 carriage bolts are course thread and are available in 10/24 thru 3/4-10 diameters and 1/2" thru 16" lengths.