This 10 in mundial steel will quickly bring dull knives to razor sharpness. Mundial diamond sharpening steels are coated with ultra fine microcrystalline diamond abrasives that make the sharpening process of your knives - honing and re-aligning the knives edges quick and easy. Every mundial product is produced under a rigorous quality control program. As proof of its commitment to quality and customer satisfaction, mundial stands behind its products, backing every one with a lifetime guarantee against defects in materials, construction and workmanship.