3M Cubitron II Roloc Fibre Discs are engineered to cut faster, cooler and with less grinding pressure than conventional abrasives. Plus they can last up to five times longer, for increased productivity.. 3M Precision-Shaped Grain (PSG) maintains super-sharp points that cut exceptionally fast with less pressure. Disc life is significantly longer, completing more vehicle parts per disc and requiring fewer disc changes. Triangular-shaped ceramic grain wears evenly, runs cool, and optimizes mineral breakdown