Lots of extra letters a numbers got added down the line.
Let's say, the '27' card, it's the 651 Compressor Time constants. It could be marked: 82E27 or 6082027ENP, in both cases these cards are pin compatible and do the same job, just built maybe 15 years apart.
For me it will be a '27 card' and in the tech world, that's the term for that card.