DMT Extra Coarse Pocket Stone DMT. This Knife Sharpener from the devoted craftsmen at DMT is a diamond stone that measures 4 3/8" x 7/8" with Black extra coarse grit and 220 mesh. Don't take the path less traveled without the DMT Extra Coarse Pocket Stone Knife Sharpener. Specifications for DMT Extra Coarse Pocket Stone: Manufacturer: DMT Sheath Material: Leather Features of DMT Extra Coarse Pocket Stone Knife Sharpener: Diamond stone measures 4 3/8" x 7/8" Black extra coarse grit 220 mesh Comes with leather sheath Hang packaged Package Contents: DMT Extra Coarse Pocket Stone DMT DMTW4X: Extra Coarse Pocket Stone