JB Distributors' 4 1/2-inch Type-27 Macro Flap Discs come in units of 10. Macro Flap Discs are 4.5 with a 7/8 arbor and ideal for rust removal, light deburring and ferrous and non ferrous metals. They are also best for welds and blending and all purpose sanding and grinding. All welders and sheet metal contractors will be very pleased with the performance of this flap discs. They are available in 40 grit, 60 grit (best seller) and 80 grit.