BOOST midsole Continental Rubber outsole Sole: Rubber Closure: Lace-Up Heel Type: Flat Shoe Width: D Imported Every detail accounted for. The proven adidas Ultraboost running shoes are built for each run on your training plan. Hundreds of BOOST capsules are fused together for incredible energy return. An adidas PRIMEKNIT upper hugs the foot to enhance every move. The Linear Energy Push system integrates with the outsole to increase stability for a responsive feel. Made with a series of recycled materials, this upper features at least 50% recycled content. This product represents just one of our solutions to help end plastic waste.