This card base is cut 5 1/2 by 8 1/2 inches, just like the standard cards. Then it is folded 2 1/8 inches in from each end, so that the ends will overlap in the middle. The rose piece of card stock is only attached to the right side of the base for opening.
I found that a 3 by 6 inch card fits very nicely into the small, check sized envelopes. I think they're just called No. 6 3/4. Dividing a 12 by 12 inch sheet of card stock into fourths makes four cards. I love making these little ones! So this card is like the last one I put up, except for being the 3 by 6 inch size.