Kotobuki King 250+1000/K-80 Combo
Double sided water stone.  Coarse 250 grit for removing knicks and fine 1000 grit for finishing.   Proper maintenance of a knife is very important.  A sharp, well honed edge is essential for a clean cut.  There are a number of ways to sharpen a knife, but water stones are the preferred method, because the user has absolute control during the sharpening process.  Japanese whetstones in particular are said to produce a finer edge than North American stones due to the unique bonding process of the stone during the manufacturing process.