Each set has 93 cards (90 normal and 3 special). Each pack of cards is 400 yen, and contains 7 cards. However, there are some cards with the same number that have different types of backgrounds (even though the picture is the same). These cards are called parallel cards. So there are actually more than 93 cards in each set.
Most of the pictures on the cards look very good. There are pictures staged in a studio, but there are also pictures that look like they come from concerts or other events. There are also some polaroids, with comments and other scribbles written in by the seiyuu.
The ColleCarA sets that have been released are as follows.
In addition to the cards themselves, there are also small plastic card cases with a picture of the seiyuu on them. But these cases are small, and cannot hold that many cards.