It's this one. Had a run for 6 years using exclusively portapros. I'm using larger cans now, but I do kind of want one of those.
Koss just came out with portapros with (partially) detachable Usb C and jack cables, if you would like something that doesn't go inside your ears.
On the same note I really like GIFGAS. Bit of the same, just with train hopping across Europe. YouTube is apparently removing some of his videos though, but all should be on his Patreon.
It's this one. Had a run for 6 years using exclusively portapros. I'm using larger cans now, but I do kind of want one of those.