The Defyance is a neutral shoe, but it has a perfect fit it provides the necessary support in the heel and metatarsus. Element an upper technology featuring superior microfibre construction to provide weather protection in a light, supple and quiet fabric that does not sacrifice breathability, durability and comfort. HPR, High performance rubber which is an abrasion-resistant rubber outsole compound that has higher durability and wears longer. Midsole and outsole components are engineered using poular technologies to set the foot in an efficient, balanced position from heel strike to toe-off, offering exceptional flexibility and an unrestricted forefoot ride. Good fit, comfort and long-lasting cushioning!  Hydroflow is the system of chambers sitting under the heel area of the midsole. As always, Brooks is a step ahead in innovative products. BioMoGo, the first fully bio-degradable midsole, sticks to the promise of our brand, an ingenious polymer structure that is more durable than EVA, offers a softer, more flexible running experience. Its properties are less temperature-related: Variations in rigidity are minimal at both high and low temperatures. A high density post, the diagonal rollbar at the medial arch is engineered for pronation control and creates a smoother transition from the midstance phase into the propulsion phase. A shank-like thermoplastic device provides torsional rigidity to the midfoot, enhancing support while allowing the heel and forefoot to act independently.