120 film generates anywhere from 10 - 16 exposures per roll, depending on the camera used. Typical sizes/ratios are 6x7cm (10 exposures), 6x6cm (12 exposures), and 6x4. 5cm (16 exposures). 220 film does not have a protective backing paper on it (allowing the longer film to fit in the same spool as 120 film).