Cushioned comfort and a natural running stride — everything you need to rack up the miles with confidence. FluidFit stretch mesh upper for adaptable reinforcement and comfort. Antimicrobial ComfortDry X-40 sockliner for a clean, dry environment. Heel and forefoot GEL Cushioning Systems absorb shock with every step. Guidance Line vertical flex groove creates a smooth, efficient running stride. Solid rubber outsole for durable traction.