Diamond knife sharpeners are very aggressive and are best for quickly setting an edge. Diamonds remove steel much faster than alumina oxide. Lansky's 4-Stone Deluxe Diamond System includes extra coarse (70 grit), coarse (120 grit), medium (280 grit) and fine (600 grit) hones for use on kitchen and regular knives. All Lansky sharpening systems include: patented precision-engineered multi-angle, flip-over knife clamp, sharpening hones on color-coded, finger-grooved safety holders, a guide rod for each honing stone, specially-formulated honing oil and extra-long knife clamp screws. Each system comes neatly packaged in a custom-molded storage/travel with complete easy-to-follow instructions.