What is the difference between the Superfeet Black, the Blue, and the Green?

The differences between the Black, the Blue, and the Green are based on the style of shoe that you put the Insoles into. The Black is for dress The Blue is great in cleated athletic footwear or casual shoes, and the Green is for any shoe that has a full-length removable insole and has room for the Insoles and the foot and still fit comfortably.