The rough side (vitrified) has 220 grits. Perfect for those that need the aggression of the 220 grit for occasional establishing of a new edge or for those that sharpen both western and Japanese knives regularly. Remember the 220grit side is not for everyday use and will wear faster. Model Characteristics Stone construction - 220 grains per sq. cm. Cleaning - NOT RECOMMENDED for Dishwasher. Hand wash with toothbrush - mild detergent. Maintenance - Occasional light sanding with fine sand paper to achieve a flat surface. Recommended for - Any metal blade Storage & use - Dry and store in waterproof box. Use near the sink with a good water supply. Unit size - L 210mm X W 66mm X H 33mm Weight - 1.1 kg Country of Origin - Japan SPECIAL NOTES: This stone CANNOT be used on ANY Ceramic knives. Special price for online orders only. No professional discount available on this item.