Dianova Lapstone Diamond knife & axe sharpeners are Swedish-made quality diamond sharpeners that will easily keep knives, axes or other tools sharp. Double-sided with a coarse and a fine side. The size of each diamond-covered side is 7.5 x 2cm. A third function comes from using either of the two rounded edges of the sharpener that serves as a steel rod for ?steeling? softer blades. The great benefit of a diamond sharpener compared with a conventional honing stone is that it can be used dry, it maintains its flat surface throughout its lifetime and it reduces the grinding time substantially. If used dry it should be washed regularly. Total length 17cm. Instructions included. Nylon sheath included.