UPC Code Rules
UPC-A barcodes have 12 digits total
S2K Rules:
1. Always Drop the last digit (on the far right) no matter what number it is
2. Drop the first digit (on the far left) ONLY if the number is a Zero (0)
3. The inner 10 digits are ALWAYS included.
UPC-E barcodes have 8
digits total
S2K Rules:
1. Include all 8 digits in S2K
2. Press the UPCe to UPCa expansion button.
