Originally posted by: wyansas
This one's F-15 and B-18, whatever that means
I can’t confirm without a shadow of a doubt, but my theory on this is that those code are the number of the actual mold used to make the shell.
When making the shells they probably use a couple molds at a time, and as time goes on they get worn out and need to be scrapped. The Quality Control folks likely put numbers on the molds to easily identify flaws during production.
Because they used multiple molds at a time a single print run can have any varying number of mold numbers, but they generally should be in the same neighborhood. For example, your Front and Eric’s front are 1 digit off. Not bad.
I believe that as time went on the numbers got higher for later games. They’re sort of a pseudo-quasi-hemi-demi-semi date stamp, and as time goes on in our hobby I think these codes might come in handy eventually (imagine if someone did a back swap on Stadium Events or NWC and it could be caught simply by that little B-x code)
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Got any of these for sale? Sell them to me. I also buy other NES Publisher inserts, and even GB/GBC, and SNES inserts too.