Kit includes premium diamond discs of 50000, 8000, 3000, 1800 grit each and 2 cerium. This professional series of diamond abrasives has an incredibly long life and excellent cost-effectiveness. Use wet (recommended) or dry. Carbide tools: perfect for ultra high-polishing carbide and non-ferrous metals. Lapidary and watch crystal: ideal uses include glass and saphire watch crystal scratch removal and polishing, lapidary, jewelry and stone inlay work. Achieves the absolute best wet-polished look on semi and precious stone, decorative glass and the like. The highest quality finishes are achieved in only 4-5 steps. Highly recommended to use with NINJA cushion item number N-3103. Disc size: 3" diameter.