hex head flange bolts material: carbon alloy steel size: 1/4"~1",M4~M24 surface: DAC,plain. zinc HDG ... Professinal manufacturer and exporter of Fasteners. 1Name hex head flange bolts 2MaterialIron,carbon steel,brass,aluminum,stainless ... ,according to the formal quotation sheet12Head typesPan head,round head,round washer head,recessed head13Drive typesSlot, Phillips, Phillips tamper-resistant ...