They are widely used as plug gages

5/8-18 x 3 1/2 Grade 5 Hex Cap Screw Plain Domestic USA (100)

threaded full length

1-8 x 1 1/4 Socket Set Screw Cup Point Alloy

5/8-18 x 3 Grade 8 Hex Cap Screw Yellow Zinc Plated Domestic USA (25)

9/16-18 x 6 Grade 8 Hex Cap Screw Yellow Zinc Plated Domestic USA (25) 7/8-9 Grade 8 Hex Cap Screws Plain - Domestic USA They are widely used as9 16 18 x 6 Grade 8 Hex Cap Screw Yellow Zinc Plated 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