Guidance Line® Vertical flex groove decouples the tooling along the line of progression for enhanced gait efficiency. * Solyte® Midsole Material A lighter weight midsole compound than ASICS" standard EVA and SpEVA®. Also features enhanced cushioning and durability. * P.H.F.® (Personal Heel Fit) 2 layers of memory foam line the collar and mold to the athlete"s heel, creating a personalized fit. * Impact Guidance System (I.G.S.®) ASICS® design philosophy that employs linked componentry to enhance the foot"s natural gait from heel strike to toe-off. * T246N