The VO2-S 90 PRO models combine the popular, stabilizing VO2 cuff with the innovative, one-sided VO2-S frame for comfortable cushioning. But that's not all. For 2022, K2 has completely revamped the upper: thinner, lighter, and more breathable, yet still offering the renowned superior fit, allowing you to really push yourself during long sessions. They are the perfect choice for ambitious fitness skaters who enjoy high speeds and appreciate smooth rolling performance. The 90 mm wheels ensure easy maneuverability and a stable ride. Power transfer is also impressive during intense training sessions. The Vortech ventilation system provides a pleasant foot climate during endurance workouts. The VO2 S 90 Pro Short Cuff is designed for those with narrow feet and low arches. The cuff, shaped for a lower calf attachment, completes the design perfectly. Good Fit, more Fun.