The PTP CoreBall is a versatile pro-grade gym ball that can be used during core stability and flexibility exercises. In particular, using a CoreBall can help activate the muscles surrounding the abdomen, the pelvic floor and the back, which act as the important foundation to all functional movements and daily activity in general. The range of exercises included will help you make the most of your CoreBall and help you correct or maintain a proper spine alignment. Incorporate a CoreBall into your exercise routine for a fun and efficient workout and discover all the benefits for yourself. This particular Steel Grey CoreBall is our largest CoreBall and features a 75 cm diameter, which makes it suitable for individuals who are over 185 cm (or almost 6 ft 1) tall. All CoreBalls come with a bonus pump for added convenience.