You will also need the extended tray to accommodate the size of the mats for the strip dies. If you can find a Quilters Edition it already comes with the longer trays and mats. If you buy Sizzix quilting dies you shouldn't have to worry much about shims and what not. If you are using other brands of dies like Accuquilt or some of Sizzix smaller paper crafting dies you will need shims. A shim can be anything like poster board or a flat rate envelope from the post office. You don't have to by the mylar shims from Sizzix unless you want to stick with their products entirely.