1"-8 x 3-1/2" Grade 9 Holo-Krome® ECOGUARD® Finish Hex Cap Screw / THREAD CLASS: 2A THREAD DIRECTION: RIGHT-HAND FASTENER LENGTH: 3.50 INCHES NOMINAL HEAD STYLE: C1 HEXAGON HEAD HEIGHT: 0.732 INCHES MINIMUM AND 0.768 INCHES MAXIMUM WIDTH BETWEEN FLATS: 1.469 INCHES MINIMUM AND 1.500 INCHES MAXIMUM END ITEM IDENTIFICATION: 2590-01-626-2713 NOMINAL THREAD DIAMETER: 1.00 INCHES THREAD QUANTITY PER INCH: 8 MINIMUM TENSILE STRENGTH: 180000 POUNDS PER SQUARE INCH HARDNESS RATING: 38.0 ROCKWELL C MINIMUM OVERALL AND 42.0 ROCKWELL C MAXIMUM PART NAME ASSIGNED BY CONTROLLING AGENCY: 1"-8X3-1/2" GRADE 9 FINISH CAP SCREW COLOR: GRAY OVERALL OR SILVER MATERIAL: STEEL OVERALL MATERIAL DOCUMENT AND CLASSIFICATION: AISI 8637/8640/8740 MEDIUM CARBON ALLOY STEEL WIRE OR 4340 ALLOY BAR STOCK,GRADE 9 ASSN STD SINGLE MATERIAL RESPONSE OVERALL SURFACE TREATMENT DOCUMENT AND CLASSIFICATION: SPECIAL ECO FINISH TO MEET 1000 HOURS OF SALT SPRAY CORROSION RESISTANCE MFR REF SINGLE TREATMENT RESPONSE OVERALL THREAD SERIES DESIGNATOR: UNC