Primeknit+ upper for breathable comfort Lace-up construction Boost midsole midsole for energy-returning comfort Stabilizing Torsion System Continental rubber outsole for extraordinary grip against wet and dry conditions The Boost cushioning you’ve known and loved for years get a major upgrade on the adidas Ultraboost 21. Now featuring 6% more Boost capsules, these supportive sneakers are more supportive, stable and comfortable than ever. Plus, their made with Primeblue so you can feel good about the kicks you rock on your feet. Product Code: S23869