5/16"-18 x 1-1/4" Yellow Zinc Finish SAE J429 Grade 5 Hex Flange Bolt / THREAD CLASS: 2A THREAD DIRECTION: RIGHT-HAND THREAD LENGTH: 1.250 INCHES NOMINAL FASTENER LENGTH: 1.250 INCHES NOMINAL HEAD STYLE: C7 HEXAGON EXTENDED WASHER HEAD HEIGHT: 0.32 INCHES MAXIMUM WIDTH BETWEEN FLATS: 0.4890 INCHES MINIMUM AND 0.5000 INCHES MAXIMUM EXTENDED WASHER DIAMETER: 0.68 INCHES MAXIMUM EXTENDED WASHER THICKNESS: 0.05 INCHES MINIMUM END ITEM IDENTIFICATION: 2320-01-465-2174 NOMINAL THREAD DIAMETER: 0.3125 INCHES THREAD QUANTITY PER INCH: 18 PART NAME ASSIGNED BY CONTROLLING AGENCY: SCREW, HEX, FLANGE COLOR: YELLOW OVERALL MATERIAL: STEEL OVERALL MATERIAL DOCUMENT AND CLASSIFICATION: SAE J429 NATIONAL STD SINGLE MATERIAL RESPONSE OVERALL SURFACE TREATMENT: ZINC OVERALL SURFACE TREATMENT DOCUMENT AND CLASSIFICATION: ASTM F1941, ZINC COATING FE/ZN, TYPE 5C ASSN STD SINGLE TREATMENT RESPONSE OVERALL THREAD SERIES DESIGNATOR: UNC