The 70 modules are composed of a 2-module start character, four 4 x 16-module data words, and a 4-module stop character. Code 49 supports the complete ASCII character set with 128 characters. The code itself can represent a total of 49 ASCII characters or 81 digits.
In Code 49, the barcodes of Code 39 and Code 128 are stacked line by line. Code 49 is therefore very compact and is characterized by a high information density. It can be read with an extended decoder using all bar code readers, although the entire stacked code must be read first.
Code 49 is used in the electronics and healthcare industries, on printed circuit boards and in integrated circuits.