1、252pcs and 338pcs are optional, both of them included 3 diameters sanding drum and grinding wheel. 2、Grit sanding bands use for smoothing surface and curved edges, polishing both soft and hard materials. 3、Manual install, labor saving, quick remove and replace, time saving. 4、The roller mandrel with self-expanding rubber cushion makes the sand belt fit closely with the mandrel. 5、Widely applied in nut-carving, wood, metal, lastics, jade, circuit board and other DIY finishing and working. Multiple specifications sanding drum and grinding wheel, easy installation, use for smoothing surface and curved edges, widely applied in nut-carving, wood, metal, lastics, jade, circuit board and other DIY finishing and working. Features: 252pcs and 338pcs are optional, both of them included 3 diameters sanding drum and grinding wheel. Grit sanding bands use for smoothing surface and curved edges, polishing both soft and hard materials. Manual install, labor saving, quick remove and replace, time saving. The roller mandrel with self-expanding rubber cushion makes the sand belt fit closely with the mandrel. Widely applied in nut-carving, wood, metal, lastics, jade, circuit board and other DIY finishing and working. Specifications: Type: Drum Sanding Kit Quantity: 252PCS, 338PCS (optional) Sanding Bands Material：Aluminum Oxide Sanding Bands Size：1/2'', 3/8'', 1/4'' Package Weight: 252g / 8.89ounces 270g / 9.52ounces Package Size: 198 * 134 * 38mm / 7.80 * 5.28 * 1.50in Packing List: 1 Kit * Drum Sanding Accessories 1 Kit * Drum Sanding Accessories