You can print 5 different sizes from this --> 2 to 3 ratio high-resolution digital JPEG.
Your Local Printer can downsize your 20x30 JPG to:
√ 6x9 inch JPEG
√ 12x18 inch JPEG
√ 16x24 inch JPEG
√ 20x30 inch JPEG
All ready to print at 300 DPI. There's no physical item. You'll be able to print it on anything you like, but I suggest good watercolor paper. Print it yourself or get it printed at your local print shop. You can also upload it to any of your favorite online printers and have them do it for you on any of their products. Some online printers are Shutterfly.com, Snapfish.com, MPix.com, etc.