Hardness for plain and zinc plated washers is HRC 38-45 and HRC 26-45 for hot-dip galvanized washers per ASTM F436

1/2-13 x 6 1/2 Hex Cap Screw SS 18-8 (A2)

1/2-13 x 7 Socket Cap Screw Alloy

1-8 x 8 Grade 8 Hex Cap Screw Yellow Zinc Plated

1 1/4-7 x 8 Socket Cap Screw Alloy

1-8 x 6 1/2 Hex Cap Screw SS 18-8 (A2) SNAPSKRU Mini Drywall Anchors Hardness for plain and zinc1 8 x 6 1 2 Hex Cap Screw SS 18 8 (A2) . 18 8 stainless steel hex cap screws will have a typical composition of 18% chromium and 8% nickel. These percentages exist in 303, 304 and 305 series stainless steels so 18 8 is used at times to designate any and all of those alloy groups. 18 8 stainless steel offers good corrosion resistance and machines easily but will over time stain in coastal environments. They are also acceptable for use in ACQ pressure