The Wusthof Combination Whetstone 1000/4000 With Base consists of a combination of different high-quality, abrasive grits. The stones have two sides – one with a fine grit and one coarse. The coarse side is used to smooth off any unevenness while the finer grit is used to hone and sharpen your knife. This whetsone includes a non-slip base which guarantees even more stability, to accompany the sharpening stone.