Abrasive disks for power-operated grinders; Abrasive disks for power-operated sanders; Abrasive wheels for power-operated grinders; Bits for power drills; Flap discs for power-operated grinders; Grinding tools for grinding machines; Metal working machines, namely, saws and cutters; Pads for floor polishing machines; Polishing system for use in single-head machines comprising grinding and polishing discs for stone profiling and edges; Power-operated abrasive wheels