DMT 12in Diamond Steel DMT. Diamond Steel Knife Sharpener. This Knife Sharpener from the good people at DMT is made with extra fine grit 1200 mesh and features a molded black plastic handle with safety guard and hanging ring. Don't explore mother nature without the DMT 12in. Diamond Steel Knife Sharpener. Features of DMT 12in. Diamond Steel Knife Sharpener: Extra fine grit 1200 mesh Molded black plastic handle with safety guard and hanging ring Long stroke capability All purpose length good for blades up to 10" Hang packaged Package Contents: DMT 12in. Diamond Steel DMT DMTDS2E: 12in Diamond Steel