After the pandemic, people are “revenge traveling” as borders around the world open up to welcome tourists again. Whether for work or pleasure, traveling feels great, but we have to keep track of the local time! 



If you’re timezone-challenged and have been stuck in a one-timezone life, a timepiece with one of the most practical complications that has ever been made might be on your list. We’re talking about the Seiko SSK, modfam.

The GMT is a very practical complication, and the new NH34 movement from Seiko is just begging to be modded! Find out here if this is fit to be your next mod.

The History of The GMT Function

GMT stands for Greenwich Mean Time and it also points to 'zero degrees' on the 24-hour international time zone chart.

In simple terms, a GMT watch is a timepiece that displays both a 24-hour and a 12-hour timescale. In addition to the local time, you can also set and view the time in another time zone with a GMT watch, with the fourth hand.



With advances in technology like railroads and the telegraph, global travel surged, and over time GMT watches gained a fanbase that needed to keep track of time in two time zones. 

Greenwich Mean Time (GMT) was born with the marine chronometer, created in the 18th century by one of the founding fathers of watchmaking, John Harrison. It was made for accurate longitudinal navigation, which isn’t possible without an accurate timekeeping device. 

Basically to know how far a ship had sailed longitudinally, accurate time at the home port was needed. 



Later, this new navigation system inspired 1884’s International Meridian Conference to establish the Greenwich Mean Time. As a result, the world is divided into 24 circumferential time zones with London’s Greenwich as the “zero degrees” meridian.

Most GMT watches today are distinguished by the use of a fourth large arrow hand, which is often given a contrasting color, to indicate GMT or home time.

The second time zone is tracked by a central hand that points to a 24-hour track on the dial or bezel, with the latter available in a fixed or rotatable configuration.

In addition, rotatable bezels add practicality in that they can be set up to indicate a third-time zone as long as you can do some quick math in your head. 

Why Get A GMT Watch?

The most obvious reason to own a GMT watch is the functional aspect of a 24 hour dial. If you are a businessman keeping in touch with your foreign clients or a frequent traveler, you will need to sport a watch with a GMT function.

It’s easy to see that no other device could be more convenient than setting a second-time zone by hand or rotating the bezel to determine the current local time at any given place in the world. 



The GMT function is one of the most straightforward and user-friendly complications that can be found in a watch.

On the other hand, you may want to get a GMT watch just because of its distinctive look, which other people pick up on. You can also find a lot of elegant GMT watches out there, with both Grand Seiko and Rolex making models that will turn heads. 

Grand Seiko even created a Seiko GMT version of its legendary 9F series quartz movement, if you need ultra-accurate timing of GMT. Of course, a Grand Seiko comes with a grand price tag – which may put some people off. 

Build Your Own GMT Watch

There is a lot of hype surrounding the Seiko NH34 GMT movement. It was first built into the 5KX case, but the future is bright for modded Seiko GMT watches with this new movement in the mix. 

Modders know that the NH34 is a more affordable alternative to the well-known Swiss GMT movements, and a super reliable alternative to generic Chinese GMT movements that may or may not work from the factory. 


Source: Chrono24


The NH34 builds on the success of the NH35 and NH36, which are known for their reliability and durability. In addition, these movements are throwaway cheap, but will still give you excellent service for years. 



We offer the new BB58 case if you want to make a Black Bay inspired GMT mod, and there are loads of other options in the works. We also have a series of GMT style bezel inserts that take design cues from some of the most popular watch designs in the world. 

The Seiko NH34 is one of the most exciting developments in Seiko mods, and promises to unlock the world of GMT watches for Seiko Mod Watches!

Wrap up

Just when you thought there would never be an affordable SKX 007 mod with GMT functionality, Seiko brings the NH34 to the table! 

We have all the watch mod parts you need to make just about any Seiko inspired mod you can imagine, and all the Watch spare parts we sell are quality assured. Check out our online catalog for more!

Happy modding!

December 17, 2022 — Jeremiah A

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