They're used to cut that image into another image you're cutting- like, using the 'Keyhole' mover n shaper to cut a keyhole shape into the middle of the 'Styled Labels' shapes. The dies made to work with the 'movers n shapers' dies have an empty space in the middle of the shape- instead of foam- so you can attach (with the wonders of magnetization) the magnet-backed die to the metal floor of the other die. It it pretty cool, in my opinion.
You COULD buy the movers n shapers base tray, which is like a (or IS, I guess) a metal tray you can put the little movers n shapers dies in, to cut- but I just have the vintage cabinet die, and use it if I want to cut the little Halloween cat or bird or the Christmas snowflakes on their own. What I'm trying to say is that if you have a die the little movers n shapers can fit in, you dont really HAVE to have the 'base tray.'
And no, you don't need a bigger die cutter, they work fine in the BigKick.
Hope this wasn't too confusing!
Edited by designguyKORY on 12-07-11 06:26 AM. Reason for edit: No reason given.