Found a review on it on "the other" shaving forum that reads this:

The hone is grey and glittery on the coarser side, and glossy black on the other. I'd estimate the coarse side something like 3-4K in waterstone grit terms. The black side is very smooth, maybe 6-8K, (just my subjective judgement based on the scratch pattern etc), but used with lather, and a light touch, I am getting a better edge off this than my 10K waterstone, which makes a more polished scratch pattern. The coarse side cuts fairly fast used dry, but taking out a nick on anything other than a really hollow blade may be a bit time consuming. For just maintaining blades though, it's great, and if I were to damage one, no doubt a rainy day could be passed sorting it out on this stone, with good results. You'd just have to use it dry, and a bit more pressure, maybe put the hone on a worksurface rather than having it on your hand.