Keep your chisels, knives, and other edge tools at their sharpest with the Combination Knife/Tool Sharpening Stone. This two sided stone features a coarse side for initial sharpening and a fine side for honing or touch ups. The stone size allows it to easily fit in your toolbox without taking up too much space. If using oil as lubricant, apply oil to surface of stone and beginworking. Apply oil on surface occasionally during use to flush away abraded material. If using water as lubricant, soak stone 15-30 mins prior to use. Continue to use water to lubricate stone.