Hardness requirements of HRB 68 - HRC 32 are met or exceeded

5/8-11 L9 Hex Collar Locknuts Cadmium Yellow & Wax Coated Domestic USA (25)

3/4-16 x 1 3/4 Socket Cap Screw Alloy

7/8-14 x 2 Hex Cap Screw SS 18-8 (A2)

5/8-11 x 3 3/4 Hex Cap Screw SS 18-8 (A2)

3/4-10 x 4 Grade 5 Hex Cap Screw Zinc Plated Domestic USA (25) Square Pancake-Head Self Drilling Screws 410 Stainless Steel Hardness requirements of HRB 683 4 10 x 4 Grade 5 Hex Cap Screw Zinc Plated Domestic USA (25) . Grade 5 Hex Cap Screws are manufactured in the USA from medium carbon steel. Our Grade 5 material meets or exceeds SAE J429 Grade 5 specifications. All products are manufactured with rolled threads. Typical hardness on diameters 1 4 to 1 inch is HRC 25 34. On diameters over 1 inch to 1 1 2 hardness will range from HRC 19 30. Tensile strength for diameters 1 4 to 1 inch is a minimum of