Drill Bits - Porcelain Tile Drill Bit - Special Spade Point with Auguer for Stone and Tile, Tungsten Carbide great for Porcelain, Grantite, Marble - 5 Pieces - by ContractorsGrade Drill Bits, Pack of 5, Sizes: 6mm, 6mm, 8mm, 10mm, 12mm Spear Point Drill Bits, Tungsten Carbide Drill Bits Special Spear Point Auger Style is Perfect for Drilling Stone Material like Tile and Marble Drill Bits Come in a plastic protective case High Strength Drill Bits for Porcelean, Marble and most other hard stones