Ceramics cut beautifully and uniformly using water (not messy oil) as the lubricant; they’re resistant to shatter and breakage and literally last a lifetime. Cleanup consists only of washing with detergent and warm water to restore the original clean, white cutting surface. The cut is rated "smooth" and you can cut Hard Arkansas with these Ceramic files. After a bit of use and a few washings, the cut will become even finer. Mfg: Spyderco SPECS: Smooth cut. Set contains 1 each of the following: Square, 1/4" (6.3mm) x 5" (15.2cm); Triangle, 1/4" (6.3mm) x 5" (15.2cm); Round, 1/4" (6.3mm) diameter x 5" (15.2cm).