The higher the number, the softer the file grit; & the lower the number, the coarser the file grit
Used for heavy product removal or for shortening artificial nails faster.
Used to take the length down and to shape side walls and free edge
Use to contour the whole nail; to prep natural nail before applying any product, also during manicure to shorten or shape natural free edge, and give a beautiful shape and nice, smooth finishing to artificial nail