DMT 8in DuoSharp Plus Coarse and extra coarse grit DMT. DuoSharp Plus Knife Sharpener. This Knife Sharpener from the knife craftsmen at DMT measures 8" x 2 5/8" with a double sided two grit diamond bench stone with a continuous zone for small and pointed tools and coarse and extra coarse grits. Don't go outside without the DMT 8in. DuoSharp Plus Knife Sharpener. Features of DMT 8in. DuoSharp Plus Knife Sharpener: Measures 8" x 2 5/8" Double sided two grit diamond bench stone with a continuous zone for small and pointed tools Coarse and extra coarse grits No base Can be used with DMTB8250 Duo Sharp Base sold separately Comes with non-slip mat Boxed with hanging tab Package Contents: DMT 8in. DuoSharp Plus DMT DMTWM8CX: 8in DuoSharp Plus Coarse and extra coarse grit