A UPC-A barcode can be augmented with a two-
digit or five-digit add-on code to form a new one. In
the examples below, the part surrounded by blue
dotted line is a UPC-A barcode while the part circled
by red dotted line is add-on code.
Enable 2-Digit Add-On Code
W206B20
*Disable 2 Digit Add-On Code
W206B00