CodaBar is a variable length symbology that allows encoding of the following 20 characters: 0123456789-$:/.+ABCD. CodaBar is commonly used in libraries, blood banks, and the air parcel business. CodaBar uses the characters A B C and D only as start and stop characters. Thus, the first and last digits of a CodaBar message must be A B C or D and the body of the message should not contain these characters. B-Coder will allow any length of CodaBar message as long as it contains valid characters and starts and ends with a valid start/stop character. If you use lower case letters for A B C or D, B-Coder will convert to upper case.