What does double or single sided mean?
When you select a single sided product your print will be printed on one side and blank on the back. For single sided prints we need one page of artwork.
When you select for double sided, this product has print on both sides and we need two files to print. The first page of your file will be classed as the front. Even if you are having the same print on both sides we still need 2 pages of artwork that show the same design.
