... manufacture of high tensile fastener,all of our bolt and nut made by 40Cr or 35CrMo,hardness HRC38-42 We have ... ,12.9 grade of track bolt and nut,plow bolt and nut,segment bolt and nut.Besides the OEM parts,we also accept ... HRC34-38Grade 12.9 170,000PSI HRC38-42Track bolt and nut,from diameter 7/16'' to 1 1/4'',from M12 ... .Thank you ! 8.8-12.9 Grade of track bolt with nut for excavator