Independently Adjustable Hour Hand (IAHH)
A watch with independently adjustable hour hand or 'IAHH' refers to the ability to move the indicated time on a watch forwards or backwards by whole hours1 without disturbing timekeeping. Every 'traveler' GMT watch has an IAHH, but there are 3-hand watche...
It can also be found on some very cheap movements but this isn’t well documented.
For example I bought a $50 brass case Timex chrono with an IHH a few years back.