The Chosera stones are markedly harder than the Super Stones. Naniwa designed these stones for professionals who put the highest daily demands on their knives. Overall, these stones are best for those who don't have a lot of time to spend and need to quickly and cleanly sharpen their knives. Every Chosera sharpening stone is delivered with a special Nagura stone (67 x 49 x 25 mm) to put a fine sharpening paste on the surface of the Chosera stones during use. This set comes with three great stones: the 1000, 3000 and 5000. This 1K stone is very popular grit because it is really starts to refine the edge. This stone is great after using the 400. If the edge is not dull or does not need a new bevel set, you don’t need to start any coarser than this. This 3k is a good final stone, many will use this after the 1000 grit stone. This stone is fine enough to be used prior to the 10000 grit stone. This 5k stone is a good final grit for many knives. This stone works well after the 1000 grit. This stone is also fine enough to be a good stone prior to the 10000 grit. Naniwa claims these are splash-and-go stones, but users say that soaking for 15 minutes really brings out the best qualities of the sharpening matrix. These stones measure 210mm x 70mm x 25mm.