The travel adjust versions are “dual position air”. The “dual air”, as Andyl correctly states, is so called because it has separate +ve and -ve air chambers.
Worth a quick call just to make sure.
EDIT: For what it’s worth, I have dual position air Revs and don’t think I’ve ever used the travel adjust in this country. Used it a few times on really long climbs in the Alps, but otherwise haven’t found it necessary.