Double row of teeth API 8 1/2" kingdream PDC bit 1-certified ... horizontal drilling and can be used for either non core, side track or recovery purposes.PDC cutters we ... Diameters5 7/8",6",6 1/2",8 1/2",9 1/2",9 5/8",9 7/8",12 1 ... Wings.Cutter Sizes5/16"(8mm),1/2"(13mm),5/8"(16mm),3/4"(19mm),etc.Suitable Formation&ApplicationVarious ... explorer well drilling. Double row of teeth API 8 1/2" kingdream PDC bit