With any of the platforms, you have to have 2 plates. In the regular length, they usually package 2 of the cutting plates. With the extended mat, if there is just one, you'll still need two and have to purchase them separately. The extended magnetic platform IS longer than the regular one!!! I think the reason for that is that Sarah Bernard? (fortunately for you, Scrapbook. com has her on a free class showing how to use her cards and the plates/magnetic mat) has those cards that need you to put all the component parts all at one time. I would recommend that you not use just one plate in the meantime, the magnetic platform is expensive and will get ruined. I have used the 2 plates from my standard length platform without a problem.