Product Advantages: Wall tile drill bits have 3-flats shank design, which is more stable when drilling, and double U-shaped grooves for quick dust removal. The triangle drill bit set can be used in concrete, tile, cement, porcelain, glass, plastic , brick, wood, ceramic pots for quick drilling. The tile bit set is industrial-strength and includes 4 different sizes of tile bits to meet your furniture installation and work needs. Tips: Please add water to assist cooling when using. Product Specifications: Material: Carbide YG6X Alloy Carbide Masonry Bits Sizes: 2 of 6mm / 1/4 Inch, 8mm / 5/16 Inch, 10mm / 3/8 Inch, 12mm / 1/2 Inch Color: Orange Package Contains: 5 x Concrete Masonry Bits with Case Tips: There may be a 1-2mm error in manual measurement, please don't mind. After-Sales Guarantee: Aracombie has a 24-hour human customer service. If you have any questions before purchasing or are not 100% satisfied with the product, please feel free to contact us, and we will provide you with solutions as soon as possible.