... chisel bits, cross bits, buttons bits, DTH bits with high, medium and low air pressure, symmetric drilling tools, eccentric drilling tools, standardized ... foundation constructions etc.Our company produces advanced drilling tools with the top-grade manufacturing equipments. The ... of the products.Tapered Drill BitType --Chisel Bits / Cross Bits / Button Bits Diameter---28mm,30mm 32mm,34mm,36mm,40mm ...