Blue Spot 19656 Metal Grinding Disc 115mm Features and Benefits:Specially designed to provide highly efficient grindingIdeal for use with normal steels, alloy steels and non-ferrous metalsHigh quality grinding disc with high resistance to breakage and long lasting durabilityDiameter: 115mm (4 1/2″) / Bore: 22.23mm / Thickness: 6mmMaximum safe speed: 13300 RPM (80m/s)Suitable for all makes of angle grindersCutting disc type: 27 A24 RBF