20 PC 2 & 4 Flute End Mill Set (70-20-201)  includes:

2 each of 2 & 4 flutes 3/16", 1/4", 5/16", 3/8", 7/16" with 3/8" shank and 1/2" and 9/16" with 1/2" shank, 5/8" and 11/16" with 5/8" shank, 3/4" with 3/4" shank

10 PC 2 & 4 Flute End Mill Set (70-20-203) includes:

2 each of 1/4", 3/8", 1/2", 5/8" and 3/4" centering cutting end mills