On's first-ever tennis competition shoe, co-created with Roger Federer. Performance experience meets performance tech.Weight: 405g100% carbon fiber Speedboard® for maximum energy returnEngineered mesh serves up breathability and supportTread pattern for grip and glideLateral and medial support for dynamic lateral movesPadded heel provides comfortable supportMidfoot cage locks feet securely in placeSize 9.5 men’s EUC, very minor wear, used once