Using precise angle guides, 100% diamond abrasive wheels and our acclaimed CrissCross™ sharpening technology, it provides a super sharp, durable, arch shaped edge with lots of “bite.” The secret is in the 100% diamond abrasive wheels which sharpen simultaneously “into” and “out-of” the edge for a superior burr-free edge that cuts effortlessly. Separate honing stage polishes the edge for flawless performance. The ProntoPro™ sharpens all quality knives including straight edge household and kitchen knives, Santoku, sports and pocket knives, as well as serrated knives. Engineered and assembled in the U.S.A.