The back designs of the Bee marked cards are in two different colours – red and blue.
The Bee marked cards are made of paper material and are poker-sized 63*88cm.
The red cards (are marked with big letter or number in the middle, or with small fonts in the corners. The marks are dark colored.
The blue cards are usually marked just with a big font in the middle. And the ink used for the marking is white or black.
The marks on the Bee marked cards can only be read by blue contact lenses. Other contacts cannot detect them.
These cards are very popular in America.