... 1.Materials: low carbon alloy steel 20MnTiB 2.Property Class:8. Standard:GB/T 1228-1231,ISO7412,DIN6914-6916, ... Bolt(T. C Bolt) For Metric Thread can meet Class 8.8, 10.9, 12.9 1, Elastic rail ... 10.9s1.Materials: low carbon alloy steel 20MnTiB2.Property Class:8.8 or 10.9s3.Appy to standard: ASTM ... head bolt: Treatment: HDG, Zinc, Black... Carbon steel: Grade/class 4.8, 5.8, 8.8, 10.9, 12.9... Stainless ...