3/8"-16 x 3/4" Zinc Finish ASTM A307 Grade A Round Head Carriage Bolt / THREAD CLASS: 2A THREAD DIRECTION: RIGHT-HAND THREAD LENGTH: 0.532 INCHES MINIMUM AND 0.551 INCHES MAXIMUM FASTENER LENGTH: 0.720 INCHES MINIMUM AND 0.770 INCHES MAXIMUM HEAD STYLE: C37 ROUND HEAD DIAMETER: 0.782 INCHES MINIMUM AND 0.844 INCHES MAXIMUM HEAD HEIGHT: 0.188 INCHES MINIMUM AND 0.208 INCHES MAXIMUM END ITEM IDENTIFICATION: F-15SA NECK LENGTH: 0.188 INCHES MINIMUM AND 0.219 INCHES MAXIMUM NOMINAL THREAD DIAMETER: 0.375 INCHES THREAD QUANTITY PER INCH: 16 NECK WIDTH: 0.368 INCHES MINIMUM AND 0.388 INCHES MAXIMUM PART NAME ASSIGNED BY CONTROLLING AGENCY: ROUND HEAD, CARRIAGE BOLT MATERIAL: STEEL OVERALL SURFACE TREATMENT: ZINC OVERALL THREAD SERIES DESIGNATOR: UNC