yourATCstore Hats, Hats and More Hats Collage Sheet. Gorgeous women wearing gorgeous hats. The average size on the images are 2 3/4 in. x 2 in., and there are also smaller images to use on your artwork too. These are still perfect size images for ATCs and perfect when using for transfering techniques. This matte finish collage sheet is professionally printed and comes in a crystal clear bag for protection. Each collage sheet measures 8 1/2" X 11" and is acid free.