Fastest grain removal in the marketplace for carbon based steels (26% more than the competition) and one of our best on stainless steels, while offering excellent life. Recommended for aggressive use and heavy duty applications. Active grinding agent provides cool cutting with light pressure. Special optimized resin bond offers maximum cutting capacity, strong edge stability and long life. Premium Zirconia Alumina grain with a poly/cotton heat treated backing. The poly/cotton combination provides low stretch and strength for the high Zirconia concentration that Z3 contains.