Smith'S Sharpening System 750grit Combines flat diamond pull- thru carbide & multi-purpose teardrop ceramic rods in one sharpener Fine 750 grit interrupted surface stone provides a quick razor sharp edge Pre-aligned carbides provide quick edge setting capabilities with 3 or 4 strokes Multi-use ceramic rods provide a smooth razor sharp edge Designed especially to sharpen straight edged knives as well as serrated edges