Franz Swaty Razor Hone in Box Vormals - eBay (item 110439415746 end time Oct-04-09 15:00:39 PDT)

I recently purchased this Franz Swaty Hone off Ebay (even if for nothing more than a neat collectible). The seller did not know the grit and there is no indication of the grit. I know it's probably a stretch, but would anyone know or be able to figure out the grit of this hone? It is about 5" in length.