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. QUICK CHANGE: The abrasive sanding discs unique safety torque spiral allows to replace disc quickly. They combine premium quality sanding grains with strong shank lock base, long lasting with high performance. 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. Colour:Photo Color Material:Zirconium Corundum Package Contents: 1 set x 40/60/80/120 Grit Grinding Wheels kit Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.