Well, if you have the 6x6 back, there is a pressure plate which can be pushed/slide across which will allow different lengths of film to be used. If you don't have the 6x6 back (i.e., you have a 6x7 back), you can buy a 120 insert and remove the 220 insert. While some people have not had problems using 120 film in a 220 back, I never had much success - the two times I tried it, the film wasn't straight the first time and was scratched the second time. It might work fine for you but on the auction site, you could buy an insert fairly cheaply.