1/2"-20 x 5-1/2" Grade 5 Zinc Finish Hex Cap Screw / THREAD CLASS: 2A THREAD DIRECTION: RIGHT-HAND THREAD LENGTH: 1.250 INCHES NOMINAL FASTENER LENGTH: 5.500 INCHES NOMINAL HEAD STYLE: C1 HEXAGON HEAD HEIGHT: 0.323 INCHES MAXIMUM WIDTH BETWEEN FLATS: 0.750 INCHES MAXIMUM NOMINAL THREAD DIAMETER: 0.500 INCHES THREAD QUANTITY PER INCH: 20 SPECIAL FEATURES: 1/2 INCH - 20 X 5-1/2 INCH GRADE 5 ZINC PLATED HEX CAP SCREW MATERIAL: STEEL OVERALL MATERIAL DOCUMENT AND CLASSIFICATION: SAE J429 GRADE 5 ASSN STD ALL MATERIAL RESPONSES OVERALL SURFACE TREATMENT: ZINC OVERALL THREAD SERIES DESIGNATOR: UNF