DMT Crystal Saver DMT. This Knife Sharpener from the knife experts at DMT smooths away chipped edges from fine crystal ceramic glassware or any hard material using coarse diamond grit. Don't go hunting without the DMT Crystal Saver Knife Sharpener. Features of DMT Crystal Saver Knife Sharpener: 4" handle 4" half round file Hang packaged Package Contents: DMT Crystal Saver DMT DMTCOO: Crystal Saver