These little buffing balls are made of a spongy nylon material similar to a pan scourer. It is impregnated with abrasive, so the effect is similar to fine emery paper. This RED course ball wheel is great for instantly removing oxide and gives a nice satin finish. You can either stop there or continue on with Tripoli and rouge for a mirror finish.Use at slower speeds, to avoid heat and reduce flying debris. Goggles or safety classes are essential. Whilst they give a great result they will wear out, so do keep a stock. Medium and fine grades are also avail be for lighter finishing jobs.