The main difference between a caller GMT watch and a flyer GMT watch is the way the second time zone is displayed. In a caller GMT watch, the second time zone is displayed by a 24-hour hand that can be adjusted independently of the other hands. This makes it easy to keep track of the time in another time zone without having to adjust the main timekeeping hands. In a flyer GMT watch, the second time zone is displayed by a 12-hour hand that is linked to the main timekeeping hands (Ed: um, not exactly. See here, here, or here.) This means that the second time zone is always displayed in the same 12-hour format as the main timekeeping hands.
Here is a table that summarizes the key differences between caller GMT watches and flyer GMT watches:
| Feature | Caller GMT Watch | Flyer GMT Watch |
| Second time zone hand | 24-hour hand, adjustable independently | 12-hour hand, linked to main timekeeping hands |
| Ease of use | Easy to keep track of time in another time zone | More difficult to keep track of time in another time zone |
| Price | Typically less expensive | Typically more expensive |
Ultimately, the best type of GMT watch for you will depend on your individual needs and preferences. If you are a frequent traveler who needs to keep track of time in multiple time zones, then a caller GMT watch may be a good option for you. If you are looking for a more traditional GMT watch that is easy to read and use, then a flyer GMT watch may be a better choice.
(Image: Bing Image Creator: “animated image of a jet pilot making a call on an old fashioned corded telephone”)