100% Synthetic Imported Rubber sole FlyteFoam Midsole Technology. 3mm of additional height on women’s models helps relieve achilles tension. FluidRide Midsole: FluidRide provides the ultimate combination of bounce back and cushioning properties with reduced weight and exceptional durability. Rearfoot and Forefoot GEL Cushioning Systems: Attenuates shock during impact and toe-off phases, and allows movement in multiple planes as the foot transitions through the gait cycle. FluidFit?Upper: ASICS FluidFit upper technology combines multi-directional stretch mesh with stretch reinforcements that adapt to the athlete’s foot, creating a truly customized glove-like fit. Heel Clutching System?Technology: Exoskeletal heel counter provides improved support and creates improved heel fitting environment.