Exercise anywhere with the Bosu Sport 55cm Balance Trainer. This This unique portable gym is easy to store and easy to take with you, but provides a wide array of efficient strength-building exercises. This half-ball, half-balance board provides a "Both Sides Up" flip that provides a greater number of exercise and training possibilities than almost any other piece of equipment. A BOSU workout helps you build core strength, balance, endurance, and flexibility while have having fun and meeting new challenges. Complete with all the necessary parts to keep you healthy and fit.