This item 1/8" (3mm) Air Micro Grinder, Pneumatic Pencil Die Grinder, 58000 RPM Free Speed Pencil Type Die Air Grinder Kit NEIKO 10649A Micro Air Die Grinder, 1/8" (3mm) Capacity, Pencil Type, 54,000 RPM, For Cleaning Dies, Rotors, Backing Plates, Brake Pads, Mounts, Etc.