... dth bits 1.flat face, concave face and drop center type. 2.Premium quality nickel-alloy steel 5"high air pressure dth bits ... 1)Design in the form of four categories: face convex type, face planar face concave and ... , spring-tooth or ball gear and spring-tooth cutter way.Our DTH Bit can be suitable for many ... types of DTH Hammer, such as XL, Mission, COP, IR, ...