Main Features 1.Grind more smoothly than angle discs with less aggressive than angle discs it's the best choice for flat surface work when using it with an Angle Grinder 2.Built for long-life premium abrasive that works well on stainless steel, hard steel, titanium and various others. 3.Zirconia Flap Disc continually produces new sharp points, creating faster cutting and a longer lifespan than aluminum oxide varieties. 4.Flap Discs consist of sanding strips adhered to a strong fiberglass backing plate in an overlapping circluar pattern. Zirconia Alumina Flap Discs Flap Discs are made from zirconia alumina, designed for high speed sanding and heavy duty removal, delivering fast and long lasting cut. Zirconia alumina abrasive provides extended service life and more cutting power than aluminum oxide, saving replacement costs and sanding time. Abrasive disc is made with fiberglass backing which supports a fast cut for grinding and finishing applications; offers extra durability and reinforcement. Overlapped abrasive strips offer more efficient sanding effect and longer service life than conventional fiber discs.