Furi Quattro Stick Pro 5-Function Diamond Sharpener First paddle sharpener with a combination of 4 flat panels and 1 round panel Cutting edges with the best manual/honing tool available today Use the 400 grit diamond panel to reshape worn/damaged edges or establish new bevel angles Progress through 500 and 500 grit diamonds to the non-diamond striated Hine panel Quattro Stick, like all Furi sharpeners, offers accuracy and ensures longevity with knives