... :40Cr 2.size:1/2''-1.1/8'' & M12 -- M36 3.mechanical grade:8.8/10. ... 9 4.case hardening:HRC38-HRC42 raw material40Cr,35CrMosize1/2''--1.1/4,M12--M36Colorblackgrade10.9/12.9handnessHRC35-42(BOLT),HRC29-36 ... bolts, masonry bolts, roofing bolts.Nuts: spring nuts, T nuts, K nuts, rivet nuts, cage nuts, lock nuts, hex nuts, hex ... of TransportationThe Best Choice for You M12-M36 and 1/2''-1.1/4'' roller bolt