5/16"-18 x 1" ASTM F593 18-8 Stainless Steel Round Head Carriage Bolt / THREAD CLASS: 2A THREAD DIRECTION: RIGHT-HAND THREAD LENGTH: 0.81 INCHES NOMINAL FASTENER LENGTH: 0.97 INCHES MINIMUM AND 1.02 INCHES MAXIMUM HEAD STYLE: C40 TRUSS HEAD DIAMETER: 0.688 INCHES MINIMUM AND 0.719 INCHES MAXIMUM HEAD HEIGHT: 0.156 INCHES MINIMUM AND 0.176 INCHES MAXIMUM END ITEM IDENTIFICATION: MRAP - COUGAR CAT1 A1 NECK LENGTH: 0.156 INCHES MINIMUM AND 0.187 INCHES MAXIMUM NOMINAL THREAD DIAMETER: 0.3125 INCHES THREAD QUANTITY PER INCH: 18 COUNTERSINK ANGLE: 15.0 DEGREES MINIMUM AND 45.0 DEGREES MAXIMUM NECK WIDTH: 0.307 INCHES MINIMUM AND 0.324 INCHES MAXIMUM MATERIAL: STEEL PROPERTY CLASS 18.8 OVERALL THREAD SERIES DESIGNATOR: UNC