Model “GMX” Pilot Junk Mill can be inserted into milling fish_top of fishes water_hole from the polit part. Model YMX Guide Mill Shoe can be used for milling inner bore and fish_top, or the unfixed fishes ( just like drill pipe, drill collar and tubing etc. ) The milling surface can be made of carbide alloy, and the water groove on mill body can make the drilling fluids flow.