Material - Made of carbon steel materials, abrasion resistance, quick change and prevent the bit from slipping, durability and long life, fast and precise to cuts a hole into wood, more convenient and secureFast and Durable - Sharpened side edges maximize carbide surfact contact for faster drilling, pointed four-corner chamfer design, tipped drill bits for ceramic tiles are easy and stable positioningEasy to Install Use - This porcelain drill bit sets is suitable for most general drill, electric drill, hand drill and bench drill, strong tungsten carbide drill bit tip and longer service life Application - For the professional machining of softwood, hardwood, mdf, timber, plywood, plastics and others wood, and ideal for drilling holes in concrete, brick, glass, ceramic, tile and cementService - We are committed to providing our customers with reliable products, if you have any questions about our products, we will respond to you within 24 hours on weekdays