20pc Wire Brush Set. Set includes 1 piece brush each in stainless steel, brass, and nylon in the following sizes: 1/4 in., 3/8 in., 1/2 in., 5/8 in., 3/4 in., and 1 in. Choice of stainless steel, brass and nylon brushes makes this kit ideal for auto-repairing and polishing.