Just use everything that is cotton - thread, fabric and batting. You do not have to buy the wrap n' zap - but - make sure the batting you use is 100% cotton. A friend of mine makes them and sells them (a bunch) and she cuts her batting the same size as her fabric. I tried and it is too difficult for me to turn and topstitch. I found that I cut my batting a good 1/2" smaller and when I turn it, it lays nicely with the seam. She makes three sizes, I prefer just the finished 10" and 8" sizes. Make sure you let folks know that they are for reheating or heating under 3 minutes (safety feature). They also are nice for keeping your dish of ice cream cold when sitting in front of tv!