Boost your expectations. Race through your training goals with soft cushioning and comfort in the adidas Ultraboost 21. These iconic runners feature the Boost cushioning system along with a stabilizing Torsion System to get after your goals confidently mile after mile. The Primeknit upper made from at least 50% Parley Ocean Plastic keeps things airy and eco-friendly while you make the most out of your daily runs. Lace closure delivers a locked-in feel. Textile lining adds soft comfort.