Unleash your speed with the Saucony Endorphin Speed 4 The Saucony Endorphin Speed 4 is designed to offer an unmatched running experience, thanks to SPEEDROLL technology and PWRRUN PB cushioning that provides exceptional rebound and energy return. Midsole and Cushioning PWRRUN PB foam in the midsole offers superior cushioning and energy return that will propel you forward with every step. SPEEDROLL technology provides a sensation of effortless speed, facilitating fluid rotation and great momentum in the step. Nylon Plate The reinvented curved nylon chassis reinforces the shoe's structure while maintaining the flexibility necessary for a comfortable and efficient run. This improved design includes a vertical gusset that adds torsional rigidity, allowing for a smooth and fast transition. Upper Details The upper of the Endorphin Speed 4 is made with a zonal engineered mesh that provides breathability and support in the necessary areas. The integrated tongue ensures a perfect fit, while the new SRS (Super Responsive Sockliner) insole adds an additional layer of comfort and response. Sole The sole of the Endorphin Speed 4 is designed to offer durability and traction on various surfaces, ensuring sure footing with every step. Sustainability The Saucony Endorphin Speed 4 are designed with sustainable materials, contributing to the reduction of environmental impact without compromising performance.