Golden tablets with the seal of the ruler that issued the pass and the seal and name of who it was issued to. About the size of your palm of solid intricately etched gold. The holder of the tablet is backed by the authority of the king to make any required purchases on credit or enter any place they deem necessary. A very powerful token indeed.
In a certain nation, no-one except the Emperor is allowed to have a name. Therefore, the people give themselves pseudo-names called "callings". Examples of callings: A family is known as the Red Sparrow family. The father is called Swooping Red Sparrow. The wife is Bright Red Sparrow Blue Lizard because she was called Bright Blue Lizard before marriage. Their daughter, until she becomes an adult, is Daughter of Red Sparrow. Their sons are Eldest Son of Red Sparrow and Younger Son of Red Sparrow.