1.Long-life, 2.High penetrability. 3.Can match many ... guarantee the high quality and reliability of the products.Tapered Drill BitType --Chisel Bits / Cross Bits / Button Bits Diameter ... )Plate ---Suitable for had rock ( more than 2067bar)Drill RodSteel Drill Rod---H19/H22, Length: 0.5M to 6.0M ... Rod---R25,R28,R32,R38,T38,T45,T51. Integral Drill Rod---H19/H22, Diameter---20mm - 42mm. tapered drill bit