2 SIZE IN 12 different diameters in one package: Black 6mm, 8mm. In addition, the 2-piece diamond drill bits are placed in 2 separate plastic boxes, which you can find and use easily. Easy OperationApplied for DRY drilling or HUMID. You can work in all conditions. The perfect tools are at your fingertips. You can also do the same great job as a master! Multiple ApplicationsPerfect for porcelain, glass brick, ceramic, ceramic tile, ceramic granite, marble, quartz, limestone, fiberglass terrazzo, masonry, quartz stone and sandstone. Reasonable sizeFor 6mm / 8 mm, Thanks to the sharp and extremely hard diamonds, the diamond drill bit ensures clean and fast professional drilling. Thanks to the high-quality industrial diamonds, the reaming drill has a fast cutting speed. High qualityThanks to the sintered diamond segment and the maximum precision, the cup wheel has a long life. Sintering makes it possible to obtain a high fracture toughness, which makes the diamond material less sensitive to shocks. It has particularly high strength and heat dissipation, which extends its service life. In addition, the cup wheel is of high quality, temperature resistant and reduces vibration