1/2"-13 x 4-1/2" Phosphate and Oil Finish SAE J429 Grade 8 Hex Flange Bolt / FASTENER LENGTH: 4.50 INCHES NOMINAL HEAD STYLE: C7 HEXAGON EXTENDED WASHER END ITEM IDENTIFICATION: 2541-01-648-8154 NOMINAL THREAD DIAMETER: 0.500 INCHES THREAD QUANTITY PER INCH: 13 PART NAME ASSIGNED BY CONTROLLING AGENCY: BOLT,HEX FLANGE MATERIAL: STEEL OVERALL MATERIAL DOCUMENT AND CLASSIFICATION: F788 ALL MATERIAL RESPONSES OVERALL THREAD SERIES DESIGNATOR: UNC