Pilot Tricone Bit for HDD Drilling Beijing Superior Drilling Equipment Co., Ltd. Base Info Model NO.:IADC537Customized:CustomizedStandard:APILength:Taper-lengthType:Center Drill BitMaterial:Tungsten CarbideUsage:Well DrillingTrademark:superiorTransport Package:Woodern BoxOrigin:Hebei Description Pre:8d Replaceable Tip Drill/Exchangeable Tip Drill Next:Trenchless Drilling Pilot Tricone Bit 91/2 Inch