Royal Mail 4-State Customer Code (RM4SCC)

RM4SCC is used by Royal Mail, Singapore Post, etc. It has one check character.

RM4SCC without Check Character

RM4SCC without Check Character is used, for example, by Dutch Post. You can also use this if you need a special way of calculating the check character. Just use this type and supply your check character as part of the data to it.