These Shape It Up nail files are made from the highest quality materials, crafted from Japanese sandpaper, there is no higher quality! The files have different grit strengths of 180 and 220 grit. These are the perfect nail files for a BIAB treatment, natural nail treatment, nail extension, manicure, or pedicure. The Shape It Up Premium Half Moon Nail File is suitable for nail products such as BIAB, gel polish, and natural nails. The 180 grit strength is medium-coarse and is excellent for perfecting artificial nails and shaping artificial nails. The 220 grit strength is fine and is good for filing natural nails without splitting them. The 220 grit strength is perfect for gently roughening natural nails, shaping natural nails, and shortening the length of natural nails. The Shape It Up half-moon nail file has a curved shape and a straight shape. You use the straight side to file crisp lines; the rounded side is perfect for working on natural nails. Besides roughening, shortening, and shaping, the curved side is also good for safely filing along the cuticles. The files are packed in sets of 10 and come in a convenient storage box.