Medalist Ceramic Alumina Resin Fiber E-ZVier Edger Flex-Loc Discs are the choice for all fiber disc grinding applications requiring aggressive cutting action, cool cut and long life. For hardest-to-grind materials. Strategically placed holes allow the operator to see the surface area being ground while the disc is spinning, enabling faster and more accurate work, and a superior finish. This product is part of the Carborundum BEST product tier group.