The MILWAUKEE 4-Piece Glass and Tile Drill Bit Set features an exact start tip for clean holes and minimal bit walking in glass and ceramic tile. Engineered with sharpened carbide, Milwaukee Glass and Tile Bits provide faster tile drilling than standard glass and tile bits. The reinforced carbide head provides increased durability when high-speed drilling into tile and glass. These bits are specifically designed for drilling holes in glass and ceramic tile with drill-drivers only, and are not recommended for use on porcelain tile.