A UPC Code (Universal Product Code) for music is the exact same type of barcode used for other products found on store shelves. To help identify the format of a music product, the RIAA established an industry standard for each music format: 2 for CDs, 4 for cassettes, 1 for vinyl LPs, or 7 for vinyl 7-inches. This recommendation is no longer necessary. The second to last number can be 0-9 for any music product. To help distinguish physical and digital product, we recommend that you treat digital, CD and vinyl as different products and use a separate barcode for each format.