Steel Dragon Tools 3-Piece 2"-4" Wet Laser Welded Diamond Core Drill Bits fit Hilti Milwaukee Rigs Five-piece wet, laser-welded diamond core bit set. Bit Sizes: 2 in., 3 in., 4 in. Drilling Depth: 16-1/4 in. Spindle Thread: 1-1/4 in. x 7 10 mm Segment Height (0.393 in.)