hex bolt 1.Surface:black,phosphated,galvanized.. 2.Grade:4 ... mild steel,45# steel,40Cr,42CrMo high strength hex bolt, hex cap bolt, balck bolt1. Surface:black oxide, phosphated,galvanized, Dacrotized2 ... , 45# steel, 40Cr, 42CrMo4. Packing: standard neutral carton box fastened with palltet5. Quality certificate:6. Supply ability: 1000 tons ... and competitive price China fastener high strength hex bolt