The Add 2 barcode is a numeric 1D barcode that encodes 2 digits of information. It is often used to provide supplemental information about other barcodes, which is why it is also referred to as an "add-on symbol". Add 2 barcodes have no error detection or correction mechanisms.
The following example barcode encodes the information 02
as an Add 2 barcode:
The Add 2 barcode encodes exactly two digits of information and has a symbol length of 25 modules. This barcode is similar to the Add 5 barcode in that they are both intended to provided supplementary information concerning a "primary" barcode.
This "primary" barcode (usually a UPC/EAN variant) would generally identify the product, while an Add 2 "add-on symbol", usually to the right of the "primary" barcode, would specify additional information such as the product's edition. 1
This can be seen in the following example:
The Add 2 barcode is managed by the GS1 (Global Standards One). 1
Add 2 barcodes are also referred to as "Two-digit add-on" barcodes.
The Add 2 barcode is similar to the Add 5 barcode in that they are both intended to act as extensions for UPC/EAN barcodes.
EAN and UPC variants (EAN-13, UPC-A, and UPC-E) are usually used as "primary" barcodes to which Add 2 barcodes would provide supplementary information.
For more information, see the Barcode Xpress SDK product page or try our online demos.