This set includes Series 303 brushes, 12 each in Round 2, Round 4, and Round 6; 6 each in Round 8, and Round 10, and Series 304 brushes, 12 each in Flat 6, Flat 8, and Flat 10; 9 brushes in Flat 12.
Brush sizes - The length and width of a brush of a given shape and size may vary by manufacturer as brush sizes are not standardized. Since fine art brushes are handmade, expect some variation even among brushes from within a single brush line.