... Grades of our materials: Different grades are available, such as K10, K20, YG8, YG6, P10, P20, YT15 ect. ISO GradeGradeDensity ( ... steelNote: Pls kindly advise the grade or using propose for quotation.Advantages of our products:high abrasion resistancelong life ... Certificate and ISO14001 Environment Management System Certificate.Strict quality control system to make sure it can match your needs ...