Meet us in the hot pursuit of the pinnacle harmonisation of weight, cushioning and responsiveness in Adidas Women’s Ultraboost 21 Running Shoes. Say hello to incredible energy return. Sock-like fit Adidas primeknit+ upper Textile lining Supportive heel counter Boost midsole 10mm midsole drop Stretchweb outsole with continental rubber Primeblue fabric Lace-up closure Adidas lep The new Torsion System provides a 15% increase in forefoot bending stiffness for a more responsive run. Incredible energy return 6% more Boost capsules ready to explode with energy in each step. Primeblue fabric This product is made with Primeblue, a high-performance recycled material.