These flap discs are ideal for finishing work in a range of metalworking applications Premium quality Zirconium grain flap discs are engineered for maximum performance stock removal, blending and finishing. The lightweight fiberglass backing absorbs vibration and makes this product incredibly strong and durable. Pro-line Zirconium flap discs are long life & suitable for a full range of metal applications including stainless steel. Abracs Zirconium Flap Discs discs are manufactured to O.S.A. Safety standards.  Features:   Suitable for a full range of metal applications  Suitable for use on stainless steel  Outstanding performance  High stock removal  Long life   Specification:  Diameter: 115mm (4½ \")  Bore: 22mm  Grit: Z40  Max. speed: 13,300RPM