Dude, I remember when I was in school, several kids "who knew they shit" would talk about 25mg Fentanyl patches, meaning the 2.5mg 72hr ones. Good thing pure Fent wasn't around, people be droppin like flies. I've actually had someone try to sell me 500mg "hydros", which were 5/500, so it seems to be somewhat common that people refer to the APAP content mistaking it for HC. I have ran CWE (with unknown true yield), and once ate what was the equivalent of 125mg HC...Knocked me on my ass, and I gots tolerance. If ever they made 500mg HC, you'd be talking about an immediate increase in deaths, prolly several hundreds per day.
I use Drugs.co/Pill-Identification-Wizard or something to that effect. Can't say how many hustlers I busted out with that trying off rip off my less-knowledgable bros (Yeah dude, that's a 10, let me type the imprint in the PC, wait, why's it say 5mg HC?) When I use to buy pharms on the street, I found a Physician's Desk Reference to be priceless in moments when internet access was not possible.