WheelNuts for Truck 1.Surface treatment Surface:Phosphated,Black oxide(black),Dacromet,Galvanized(Yellow/Silver),plate (yellow) zine plate( sliver). 2.Tensile stength: 1002N/mm 3..Quality grade canbe 8.8 10.9 12.9,according to dirrerent material . Special service:we can produce according to your sample or drawing . Competitive and reasonable price with hight quality.