For incredibly sharp Santoku and other double edged Asian style knives Two stages, sharpening and honing, for sharper, longer-lasting edges 100% diamond abrasives for faster manual sharpening Diamond abrasives will sharpen any alloy Diamonds are the most durable abrasive - they last and last Precision roller guides control the angle for razor-sharp 15 Degree edges every time Built-in versatility; can be used right or left-handed