Adizero Ubersonic 4 tennis sneakers Never worn outside and worn minimally inside Lightweight Lightstrike cushioning keeps you low to the ground and ready for every point. A reinforced stretch-woven upper locks you in when it´s time to move. The grippy rubber outsole is specially designed for traction on hard courts. This shoe is made with high-performance recycled materials and features an upper made with 50% recycled content.