Core Ball Exercise Program by G2 Lifestyles The Self-Guiding Core Ball Exercise Program by G2 Lifestyles is the world's first self-guiding fitness ball that not only focuses on strengthening your core, but also increases flexibility and improves your overall stamina. Having a strong and healthy core is the foundation for strength and endurance when exercising the entire body. The G2 Lifestyles Self-Guiding Core Ball is a fun and easy way to add a new challenge to your workout. With 12 Essential Core Ball, physician-certified exercises printed around the ball, this exercise program is designed to enhance core muscles, improve endurance and stamina, and allows you to achieve better posture, balance and coordination, helping you stand taller and look leaner. Using pthalate-free and non-toxic PVC combined with anti-burst technology, the core ball is lightweight, long-lasting and durable to meet your yoga and exercise needs. An easy-to-use pump is included, allowing for travel and storage. Enjoy instructional videos available online to get the most out of your core ball exercise program. Available in Red and Charcoal Grey, as well as the following sizes: 55cm diameter (heights up to 5'8) 65cm diameter (heights 5'9 and taller)