Fizik’s Terra X4 Powerstrap is a gravel cycling shoe with an innovative Powerstrap Velcro closure system design for an enveloping fit and a X4 outsole targeted stiffness and rubber tread for mixed surfaces. While most traditional Velcro closures just pull together two sides of the shoe's upper, in the Powerstrap configuration a ribbon wraps around the foot, providing secure containment using just two straps. The instep and the midfoot are separately adjustable for customized fit and compression. For these versatile shoes Fizik developed a specific outsole, the X4: a carefully considered combination of stiffness and comfort, to turn pedals effectively on mixed surfaces; blending nylon, with targeted stiffness, and a rubber tread for effective grip and durability.