Abrasive belts for power-operated sanders; Abrasive blast cleaning machines; Abrasive disks for power-operated grinders; Abrasive disks for power-operated sanders; Abrasive wheels for power-operated grinders; Polishing discs for automated wet-polishing multi-head machines; Polishing system for use in single-head machines comprising grinding and polishing discs for stone profiling and edges; Power-operated abrasive wheels; Power-operated grinding wheels; Sanding pads for power-operated sanders