Bobbing Compound: A very aggressive, fast cutting compound. Use as a pre-polish step. It adheres well to buffs or lap wheels. Metal Used On: Gold, silver, brass, copper, aluminum and other soft, non-ferrous metals. Results: Leaves a smooth, uniform finish that is needed before a second step or final polish. Does not leave a shine. Type of Buffs: Treated or tight muslin, medium to hard felt. Bar Size: 1 pound.