4X6 Flyers also called 4x6 Postcards are by far the most popular size of all. Our 4x6 flyers are printed on both sides on a 12PT glossy card stock with UV Gloss coating. Only have a one-side? That is ok. Just choose that in the options so that we can be sure not to UV the back so that you can easily write important info on the back. The flyer will print at approximately 4x6 and will be trimmed down from there.