MIZUNO ENERZY (FOAM): Offering versatility in its application, while still maintaining softness and resilience. It will help enhance performance capabilities. Foam Wave: A Wave of comfort made of 2 layers of foam. Top layer is U4icX and bottom layer Mizuno Enerzy Foam Wave: A Wave of comfort made of 2 layers of foam. Top layer is U4icX and bottom layer Mizuno Enerzy Rock Plate: Designed to protect your foot from sharp objects, rocks or roots while you are on the trail. Woven Upper: Soft, breathable, light woven material.