Sierra says: Designed primarily for tighter fitting footwear, Superfeet BLUE is our most versatile product. Ideal for Low to Medium Arch shaped feet that cannot tolerate maximum support. Recommended footwear: Cleated athletic footwear and all types of Casual and Dress shoes.

Sierra says: Designed primarily for footwear with a removable insole, Superfeet GREEN provides maximum support and shock absorption. Ideal for Medium to High arch shaped feet. Recommended footwear: Ski, Snowboarding, Run, Hike, and Walking.