Hardness: Rockwell C45-53

3/8-24 x 3 1/2 Grade 8 Hex Cap Screw Plain Domestic USA (50)

1 1/2-6 x 4 L9 Hex Cap Screw Yellow Zinc Plated Domestic USA (5)

5/8-18 x 3 Hex Cap Screw SS 18-8 (A2)

21/64 Heavy Duty Jobber Drill Bit

5/8-18 x 5 1/2 Grade 8 Hex Cap Screw Plain Domestic USA (25) 9/16-12 Hex Cap Screws 316 Stainless Steel Hardness: Rockwell C45-535 8 18 x 5 1 2 Grade 8 Hex Cap Screw Plain Domestic USA (25). Grade 8 Hex Cap Screws are manufactured in the USA from medium carbon alloy steel. In diameters 1 4 to 1 1 2 inches our Grade 8 material meets or exceeds SAE J429 Grade 8 specifications. Diameters over 1 1 2 inches meet or exceed ASTM A354 Grade BD. All material is manufactured with rolled threads. Yellow zinc plated bolting will meet or exceed ASTM F1941. Typical hardness on diameters 1 4