The coarse 150 grit lighter side is for final honing or touchups and the fine 240 grit dark side is for basic sharpening, removing nicks etc. Ideal size for bench work Measures 6" x 2" x 1" Intended for sharpening all types of tools and knives. 6-Inch aluminum oxide sharpening stone is a 2 sided stone with one coarse grit and one fine grit side. Intended for sharpening all types of edged tools and knives. Ideal size and convenient for bench work. This stone uses oil as a lubricant. Immerse the stone for 1 minute to fill it and apply oil on the surface occasionally during use to flush away abraded material.