(Ships rolled up, as pictured- click on picture on left to see it in use) I would never go without this! This sheet allows you to lay out all of your pieces to be appliqued and iron them together. After it has cooled, simply pull the applique off like one, big sticker! Then you can very easily center it on your quilt! The 18" x 20" is my favorite, since it is long enough to even piece together the Straddling characters. And they can even be used for other crafts like painting or as a BAKING SHEET for clay or other projects!