Medium = 23″ total spine length | 18.25″ spine between the rolls | 18″ across seat
Large = 25″ total spine length | 19.5″ spine between the rolls | 18.5″ across seat
Medium = 23″ total spine length | 18.25″ spine between the rolls | 18″ across seat
Large = 25″ total spine length | 19.5″ spine between the rolls | 18.5″ across seat