adidas PRIMEKNIT textile upper Lace closure BOOST midsole 50% of the yarn is recycled polyester The Definition Of Comfort May As Well Be Ultraboost. This Version Of The Adidas Shoes Takes The Energy-Returning Feel They're Known For And Turns It Up A Notch. Boost In The Midsole Is Wrapped In Stretchweb To Amplify That Walking-On-A-Trampoline Feeling, And An Adidas Primeknit Upper Hugs The Foot. No Running Required. This Pair Is Geared Toward Day-To-Day Wear.