Boasting Rearfoot and Forefoot GEL® Cushioning and a bouncy SpEVA® midsole, the GEL-Flux™ 2 is athletic, cushioned, and even a little bit peppy. The new upper is built with supportive synthetic overlays and a breathable mesh for optimal fit and comfort, while the Guidance Line® and Guidance Trusstic System® keep the ride smooth and efficient. Weight: 11.0 oz. Heel Height: 23mm. Forefoot Height: 13mm.