12 Contemporary Art Blank Birthday / Greeting Cards Product is as shown in the image. Cards come supplied with matching envelopes. Cards are blank inside for your own personal message. Packs made exclusively by Greetingsbox. Card Sizes are: 21.5cm (8.5") x 15.2cm (6") (Large US Letter) or 16cm (6.5") x 16cm (6.5") (Large US Letter).