Natural "Ocean Blue" Sharpening Honing Pocket Stone Waterstone Grit 12000 (Ultra Fine) for Hunters Fishermen Tourists 4.0"x1.6"x0.6" (100x40x15mm) +/-3%; grit ~12000 (ultra fine); includes: genuine leather case Natural "Ocean Blue" Tsushima sharpening honing pocket waterstone whetstone Used for honing and sharpening knives, chisels, gouges, razors, blades, planes; no pre-soaking required Medium hard, very dense, uniform consistency of ultra fine grit; longer life cutting edge; high dish resistance, long lifetime Quarried from a now closed underwater mine near South Tsushima Island, Japan; golden stamp of authenticity; very limited stock