13 x 18 15 x 21 18 x 18 18 x 24 20 x 20 20 x 25 21 x 30 24 x 30 25 x 25 30 x 30 30 x 40 30 x 42 30 x 45 35 x 35 35 x 45 35 x 50 40 x 40 40 x 50 40 x 60 50 x 60