"Why we're ALL IN: Enhance your workouts with a stability ball that helps you build back and core strength by adding balance and resistance to increase muscle activation. The ball comes in three different sizes to accommodate a wide range of different heights so you can find just the right fit for your body.The 55 cm ball is rmended for heights 5'0"" to 5'5"", the 65 cm ball is rmended for heights 5'6"" to 5'11"" and the 75 cm ball is rmended for heights 6'0"" to 6'5"". Each anti-burst ball comes with a pump for easy inflation and an exercise guide to help you get started — or continue on — your journey to feeling and being your best self. When families come together to discover the joy of staying active, All in Motion is there to make it easy and comfortable to embrace a bustling lifestyle. From running errands to running intervals, the collection AIMs to propel you forward with thoughtfully designed pieces that fit and feel great — movement is the core of this performance line, with a 100percent satisfaction guarantee. Size: 55cm. Gender: unisex. Age Group: adult."