Hot-Dip Galvanized material will meet or exceed ASTM A153

#39 Heavy Duty Drill Bit - Stubby Length

The zinc plating provides a protective layer that enhances resistance against moisture

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

1-8 x 2 1/2 Socket Cap Screw Alloy

1-8 x 2 1/2 Socket Cap Screw Alloy 5/8-11 Grade 5 Hex Cap Screws Zinc Plated Hot-Dip Galvanized material will meet1 8 x 2 1 2 Socket Cap Screw Alloy . Alloy Socket Head Cap Screws from Brighton Best. Hardness of RC 38 43, meets or exceeds ASTM A574. Manufactured from heat treated alloy steel, 1960 series.