I bought the laminator at a yard sale for $1. It sat in the garage for a long time and then we needed it for a fun project at work. I got it out, googled the refills and ordered them from Amazon. I brought the laminator and the refill to work and one afternoon when we had an hour to spare, we decided to try and make it work thinking it would take that long to get the old cartridge out, put in the new one, and make it work correctly. WE WERE WRONG!!! The old slipped out, the new slipped in and we were laminating (without air bubbles) in less than 5 minutes!! This is one of the best buys I've gotten this year!