Original sentence: A more common format of 193MB (21 mins), which has the same data density as a 650 MB full-sized CD, and 210Mb (24 mins), with the same data density as a 700MB full sized CD, used for "Pocket" data storage
Edited sentence: A more common format of 193MB (21 mins) and 210Mb (24 mins) used for "Pocket" data storage before the Flash memory era