Exceptionally Hard and Strong Abrasive Grain Fast, efficient stock removal makes 3M™ Cubitron™ II Hookit™ Cloth Disc 900DZ one of best 3M discs for metal fabrication, woodworking, paint prep and composite applications. 3M Precision-Shaped Grain exceeds both aluminum oxide and silicon carbide mineral in cut-rate and durability. Its open coat construction resists accumulation of sawdust and other sanding debris. This allows the cutting edge of the grain to continue cutting efficiently, self-fracturing to expose fresh cutting edges. Neutralize Swarf, Keep Cutting Fast An anti-static treatment neutralizes the electrical charge generated by sanding, especially on wood. Static charged swarf tends to cling to the surface of the disc, the workpiece and the machinery when sanding. Coarse or fine or powdery, dust degrades performances and productivity. In concert with this disc's open coat abrasive, loading issues are minimized, keeping 3M™ Cubitron™ II Hookit™ Cloth Disc 900DZ cutting fast. Fast, Easy Disc Changes Simple, swift and secure, the 3M™ Hookit™ attachment system just works. The soft side of a 3M™ Hookit™ disc is covered with loops while its rougher mate has J-shaped hooks. When pressed together the two cling, secure even in rugged applications. They separate cleanly and easily and 3M™ Hookit™ discs can be re-used for the extent of their abrasive life.