Designed to offer the user greater stability than a conventional, this spherical exercise or therapy ball, the 700mm Physio Roll Exercise Ball can be used for a wide variety of exercises but it will only roll in a more controllable forwards and backwards motion.This helps to build user confidence and to focus effort on specific parts of the body without having to worry about lateral balance. This blue 700mm (27.5\") diameter Physio Roll Exercise Ball, is the larger of the two sizes available ( a smaller 550mm (21.5\") diameter yellow version is also available in this section of our shop) and is very strong with a maximum user weight of 300kgs (47 st), which gives the therapist or physio the option to sit with the user on the Physio Roll Exercise Ball in situations where the user requires more support.