Will start with I hate ISO numbers. As an insert maker they just do not work and arguments against the standard fell on deaf ears.
Crazy things happened here. Metric vs USA, all kinds of personal or loyalty shit. So we have a mess.
But many do like it and you have to go with making it easy for the paying customer despite any personal preference.
Some buy ISO and a 432 callout makes no sense to them. They have no idea if this will fit or work so they will go elsewhere.
I'm not going to order a box of inserts if not sure it fits or maybe from something I found on the net.
Both numbers assure the customer just what is in the tray and that it will bolt in and do the job.
Yes this is a mess but it's the deal.
To the OP, do everything you can to make it easy peasy for buyers no matter the letters and numbers.
080408 is a standard callout and just as valid as a 432. You want both to show up in a google search.
Bob