The athletic Asics GEL Flux 2 boasts shock absorbing GEL cushioning and a bouncy SpEVA midsole, along with the optimal fit and comfort of a breathable and supportive upper. Guidance Line and Guidance Trusstic keep the ride smooth and efficient for underpronators to mild overpronators. Heel height: 22 mm forefoot height: 12 mm. Pronation suitability: Underpronator to neutral to mild overpronator APMA Seal of Acceptance. Breathable mesh upper with supportive synthetic overlays for optimal fit and comfort. Rearfoot and Forefoot GEL Cushioning Systems: Attenuates shock during impact and toe off phases allows movement in multiple planes as the foot transitions through the gait cycle. SpEVA midsole material improves bounce back characteristics and decreases midsole breakdown. Guidance Line: Vertical flex groove decouples the tooling along the line of progression for enhanced gait efficiency and a smooth ride. Guidance Trusstic System: Integrates Guidance Line construction for enhanced gait efficiency, while providing midfoot structural integrity. DuraSponge rubber outsole: AHAR Asics High Abrasion Rubber blown rubber compound for enhanced cushioning and durability in the forefoot.