... , eccentric drilling tools, standardized API system casings, bit shanks and casing tubes which are fit for hydraulic ... of the products.Tapered Drill BitType --Chisel Bits / Cross Bits / Button Bits Diameter---28mm,30mm 32mm,34mm, ... R38,T38,T45,T51Face Shape---Plate, Concave, Convex.Bit Shank & Coupling sleeve---R22,R25,R28,R32,R38 ... H19/H22, Length: 0.5M to 6.0M.Thread Rod---R25,R28,R32,R38,T38,T45,T51. ...