The BORA 8-Inch extra hard aluminum oxide sharpening stone is a double sided stone with one coarse grit and one fine grit side. Intended to remove smaller nicks and finish sharpening of all types of edged tools, camping knifes, kitchen scissors, and chisel blades. 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.