DMT Dia-Sharp Credit Card Sharpener 3 inch Set of 3 w/Case DM. Take your sharpening anywhere with the ready-to-go Dia-Sharp credit card sized diamond sharpener. Fits easily in pocket or wallet. Comes in convenient vinyl color-coded carry case. Offered in coarse fine and extra-fine diamond grits. Specifications for DMT Dia-Sharp Credit Card Sharpener: Manufacturer: DMT Additional Features: Set of 3 w/Case Features of DMT Dia-Sharp Credit Card Sharpener: Pocket-sized convenience Three different diamond stones: Extra-Fine to polish and refine an edge Fine for a razor sharp edge and Coarse to transform a dull edge Sharpens knives faster than conventional stones with DMT's micronized monocrystalline diamond surface No oil is needed-sharpen dry or with water Durable construction will provide years of performance and reliable service Package Contents: DMT Dia-Sharp Credit Card Sharpener DMT DMD3EFC: Dia-Sharp Credit Card Sharpener 3 inch Set of 3 w/Case