This will be a BUR but I'd like some opinions first.
We have a K701 tag which is popular because it's Akiyama Mio's headphone of choice.
We've also got very small K702 and K712 tags. We also have an AKG tag which is probably useless.
For post #990066, I'd guess the distinction was made based on the coloring? but given artistic license with respect to colors and the very small difference to begin with, I don't think it's productive to separate based on that. For post #1010688, the artist commentary says K701 but it's tagged as K702.
The K712 tags appear to be (in all 2 cases) because the model number is visible on the headphones in the pictures.
All these headphones have essentially identical physical structure -- and I say that even having handled some of them IRL. They sound different, and some have different materials or open/closed backs, but as far as art is concerned they should share a single tag IMO. I'm not quite sure what to call that tag. I do feel the design as a whole is distinctive and iconic enough to be worth tagging.
The thing that started me on this train of thought was trying to figure out what to tag the headphones on post #6625404. Bocchi is often seen with headphones that look like some kind of AKG K-series, but I don't think there's enough detail to tell for sure which model. I don't want to tag it K701 because it probably isn't, but I want to tag it something.