The LA-145 Leather Honing Wheel is used with PA-70 Honing Compound. Honing your tool on the leather honing wheel after sharpening gives you maximum sharpness for your edge tool. Honing highly improves edge retention and provides excellent maintenance. You can quickly and easily realign the edge against the leather honing wheel between sharpenings. When the honing wheel is new, impregnate it with light machine oil before applying the honing compound so as to extend its service life and get the best performance.