4 Piece, Glass & Tile Bit Set, Precision Tip Solves Bit Wander & Bit Walking, High Quality Carbide Tip With Reinforced Head Prevents Bit Cracking & Provides A Longer Life, 3 Flat Shank To Prevent Slippage, Innovative Geometry Allows Bit To Drill Faster, Set Consists Of The Following Sizes: 1/8", 3/16" 1/4" & 5/16".