Our 48-20-8983 Milwaukee 5/16'' Glass and Tile Bit features an exact start tip for clean holes and minimal bit walking in glass and ceramic tile. Engineered with sharpened carbide, 48-20-8983 Milwaukee 5/16'' Glass and Tile Bits provide faster tile drilling than standard glass and tile bits. We've designed these bits with a reinforced carbide head for increased durability when high-speed drilling into tile and glass. We've specifically designed these bits for drilling holes in glass and ceramic tile with drill-drivers only. We don't recommend these bits for use on porcelain tile.