QUICK CHANGE: The abrasive sanding discs safety torque spiral allows to replace disc quickly. They combine premium quality sanding grains with strong shank lock base, long lasting with high performance. 40 pcs 2 inch quick change flap discs, 40/60/80/120 grit, 10 pcs of each grit, 1pc 1/4 inch shank holder. 41 pcs in total. Maximum RPM: 12,000 to 14,000. HIGHER PERFORMANCE: These roll lock sanding discs made of zirconia alumina grains, with features good hardness and wear resistance, compared with alumina grinding disc, the zirconia grinding discs have better grinding efficiency and service life. WIDE APPLICATIONS: Die grinder flap discs great for using on surfaces of plastic, stainless steel, alloy, iron, non-ferrous materials and other nonmetal materials like wood, glass, ceramics, stone. Compatible with any 1/4 inch power drill, air grinding drill, die grinder, and other rotary tools., Weight: 1.45284630658 pounds, Manufacturer: Omvial