About this item [(Multifunctional Drill Bits)] The triangular tungsten carbide bits are designed to drill through the toughest materials such as Ceramic, Glass, Granite, Marble and Porcelain. In addition, they can also be used to drill through softer materials such as wood, brick and concrete. [(U-shaped Spiral Design)] U-shaped spiral design reduces rotation resistance, improves drilling efficiency, helps remove the waste material efficiently. [(Premium Material)] The tile drill bits are made of high quality tungsten carbide material, which is high hardness, wear-resistant, and durable. Ideal for profession or DIY drilling work. [(Fast Chip Removal)] Adopts spiral slot design,makes the drill bit smoother, easy to position and conducive to fast drilling, fast removal of thread chips,improves the efficiency of drilling.