Large hexagon head bolt with nut and washer 1.Certificate:ISO9001:2008. 2.Also by customer's ... ,bolts,nuts,rail pad,washer,fish plate and insulator.Steel structure Hexagon bolt with nut and washerTypeGradeMaterialSpecificationHardnessBolt10.9S20MnTiBM12-M30HRC33-3935VB8.8S40BHRC24-3145#35 ... #,35#12-30(mm)HRC35-45 Large hexagon head bolt with nut and washer