To be used with right angle grinders 3M Precision Shaped Ceramic Grain (PSG) maintains super-sharp points that cut exceptionally fast with less pressure PSG runs cooler and disc life is significantly longer, completing more parts per disc and requiring fewer disc changes Stiff fiber backing and a strong resin bond provide durability and tear-resistance for heavyweight applications such as high-pressure weld grinding or beveling Grinding aid incorporated on the disc minimizes grinding temperatures for heat-sensitive alloys 3M™ Cubitron™ II Fibre Disc 987C with our exceptionally high-performing 3M Precision Shaped Ceramic Grain combined with stiff fibre backing offers significant gains in productivity on medium to heavy-duty operations. This disc achieves a higher cut-rate, greater durability and longer life than other fiber discs—all with less grinding pressure.