tension nut material:ductile iron 65-45-12 tapped thread:3/4-10 5/8- ... iron, ductile iron, brass, bronze, and other special steel materials.2) Usage: auto & motorcycle, mining machinery, engineering machinery, agricultural equipment, construction, electric appliance, military equipment ... -galvanized, sandblasting, painting, powder-coating.7) Accuracy±0.01mm ductile iron tension nut