Once a feeble dream of our ancestors, our world has become increasingly interconnected. We can communicate and interact with people in different countries in the space of a few seconds. We can travel to other nations in just a few hours or a few days. No longer confined to a single time zone, our lives often bridge continents and cultures.
As such, time has become a global currency. The GMT watch, a horological marvel, has become an indispensable tool for determining the time in different places.
Let's discuss more about GMT watches, exploring their history, mechanics, and the myriad reasons why they have become essential accessories for those who value precision and style.
What is a GMT Watch?
A GMT watch is a timepiece that allows you to display two different time zones simultaneously.
What does GMT mean? "GMT" means "Greenwich Mean Time," the standard time reference used worldwide.
A GMT watch does not exclusively show Greenwich Mean Time. Rather, it has an additional 24-hour hand that can be independently adjusted to indicate a second-time zone.
What are the General Characteristics of GMT Watches?
While there are several brands and models of GMT watches, they share the same general features:
- Additional 24-hour hand: This hand completes one full rotation in 24 hours, indicating a second time zone.
- 24-hour bezel: Many GMT watches feature a rotating bezel with a 24-hour scale. Rotating the bezel allows users to align the scale with the GMT hand, providing an easy way to track different time zones.
- Independent hand adjustment: The GMT hand can often be adjusted independently of the standard hour and minute hands, allowing you to set it to any time zone without affecting the local time display.
- Clear time zone differentiation: The watch's design usually incorporates elements to visually distinguish between the two time zones such as different hand styles or color-coded bezels.
- Crown and Pushers: These are used to set the time and adjust the GMT hand. In mechanical watches, adjusting the GMT hand might involve pulling out the crown to a specific position. In quartz watches, pushers or a digital interface might be used.
Who Uses GMT Watches?
GMT watches were originally designed for airline pilots since they frequently cross time zones and need to keep track of multiple time zones simultaneously.
This feature extended its utility far beyond aviation. Today, GMT watches are popular among:
- Frequent travelers: Whether for business or leisure, staying in sync with their destination or home time zone is important.
- Global business professionals: Coordinating meetings across different time zones is essential.
- Shift workers: Managing work and personal schedules becomes easier with a GMT watch.
- People with loved ones in different time zones: Staying connected with family and friends is facilitated.
Anyone who needs to keep track of two different time zones can benefit from a GMT watch.
How Does a GMT Watch Work?
GMT watches can either be mechanical or quartz. Let's see how both work
Mechanical GMT Watches
- Movement Mechanism: Mechanical GMT watches use a movement (either automatic or manual) that relies on a complex system of gears and springs. The mainspring, escapement, and balance wheel work together to regulate the passage of time.
- GMT Hand Geartrain: A separate geartrain drives the GMT hand to rotate once every 24 hours. This geartrain is often connected to the hour wheel but modified to complete a full rotation in 24 hours rather than the standard 12-hour cycle.
- Adjusting the GMT Hand: Many mechanical GMT watches allow the GMT hand to be adjusted independently from the main hour hand. This is done through a dedicated crown position or adjustment screw that changes the position of the GMT hand relative to the hour hand.
Quartz GMT Watches
- Electronic Movement: Quartz GMT watches, or automatic GMT watches, use a battery-powered movement with a quartz crystal oscillator to regulate time. The quartz crystal vibrates at a precise frequency when an electric current passes through it.
- GMT Function Integration: In quartz GMT watches, the GMT hand is driven by a stepper motor, which is controlled by the electronic circuitry. The GMT hand typically moves in 24-hour increments and can be adjusted either manually or automatically through the watch's settings.
- Digital Adjustment: Many quartz GMT watches have digital settings that allow you to adjust the GMT hand by simply pressing buttons or using a digital interface. This is often more straightforward than mechanical adjustments.
How Do You Set a GMT Watch?
Here’s a step-by-step guide on how to set a GMT watch.
1. Understand the watch functions.
Locate the following components on your watch:
- Main Hour Hand: Indicates the local time
- GMT Hand: A 24-hour hand that shows the time in a second time zone
- 24-Hour Scale: Found on the dial or bezel, used to read the GMT time
2. Set the local time.
- Pull out the crown: The crown is usually located on the side of the watch and is used to adjust the time. Depending on your watch model, pull it out to the second or third position. This position is typically for setting the main hour and minute hands.
- Set the main hour and minute hands: Rotate the crown to set the main hour and minute hands to the correct local time.
- Push the crown back in: After setting the local time, push the crown back to its normal position. This position locks in the time and ensures the watch keeps accurate time.
3. Set the GMT hand.
How to set the GMT hand depends on whether your GMT watch has an independent GMT hand adjustment or uses a rotating bezel.
If the GMT hand is independent:
- Pull out the crown: Pull out the crown to the position used for setting the GMT hand. Some watches have a separate pusher or screw-down adjustment for this function.
- Adjust the GMT hand: Rotate the crown or adjust the pusher to move the GMT hand to the desired time zone. This time zone is often set to your home time or another reference time.
- Push the crown back in: Ensure the GMT hand is correctly positioned then push the crown back to its original position to lock in the setting.
If the GMT hand uses a rotating bezel:
- Set the GMT Hand: Set the GMT hand to the current time in the second time zone. Rotate the GMT hand or align it with the 24-hour scale on the bezel.
- Adjust the bezel: Rotate the 24-hour bezel so that it aligns with the GMT hand. The bezel’s 24-hour markings allow you to read the time in the second time zone relative to the GMT hand.
4. Synchronize time zones.
- Check the time in both zones: The GMT hand and the local time (main hour hand) should be correctly set and synchronized. Ensure that the 24-hour scale or bezel correctly reflects the time difference between the two time zones.
- Adjust as needed: If you are traveling or working in a new time zone, adjust the GMT hand or the bezel accordingly.
5. Do a final check.
- Check the day/night indicator: If your GMT watch features a day/night indicator, make sure it correctly shows AM or PM for the GMT time zone.
- Secure the crown: If your GMT watch has a screw-down crown, screw it down tightly to maintain water resistance and protect the movement.
How To Use GMT Watches?
Reading a GMT watch is straightforward once you understand its components.
Local Time: Look at the standard hour and minute hands to determine the current time in your location.
Second Time Zone
With a 24-hour bezel: Rotate the bezel until the city or time zone you want to track aligns with the GMT hand. The GMT hand will then point to the time in that time zone on the 24-hour scale.
Without a 24-hour bezel: The GMT hand itself indicates the time in the second time zone. Remember, it uses a 24-hour format, so 13 represents 1 PM, 22 represents 10 PM, and so on.
Let's say you're in New York and want to know the time in Tokyo.
The standard hands show it's 3 PM in New York.
Rotate the bezel until Tokyo aligns with the GMT hand.
The GMT hand points to 12 on the 24-hour scale, which corresponds to 12 AM in Tokyo.
Therefore, it's 3 PM in New York and 12 AM in Tokyo.
Remember that the GMT hand always moves in 24-hour increments, regardless of whether the watch has a 12-hour or 24-hour dial.
How Does the GMT Bezel Work?
The GMT bezel is a simple yet valuable tool for tracking a second or even third time zone. It's a rotating outer ring on the watch case that features a 24-hour scale, usually divided into day and night sections for better visibility. Let's do a short review on how to set the bezel.
- Set the GMT hand: Align the GMT hand with your home time or any other reference time zone.
- Rotate the bezel: Turn the bezel until the city or time zone you want to track aligns with the GMT hand.
The GMT bezel then acts as a visual reference. The position of the GMT hand on the bezel indicates the time in the corresponding time zone.
The GMT bezel is bidirectional. This means you can rotate it clockwise or counterclockwise.
It's often divided into day and night sections for easier time differentiation.
Some watches may have a fixed bezel with a 24-hour scale printed on the dial instead of a rotating bezel.
Additional Tips
- Practice using the GMT bezel to get comfortable with it.
- Many watch enthusiasts find it helpful to set the GMT hand to their home time and use the bezel to track their current location.
- Some watches offer even more advanced GMT functions such as the ability to track a third time zone using the bezel in conjunction with the GMT hand.
What Are the Different Types of GMT Watches?
There are primarily two main types of GMT watches based on how their hands operate:
1. Office GMT (Caller GMT)
- The 24-hour hand can be adjusted independently.
- Often used for business purposes where you need to track a specific time zone (like your office or home) while in a different location.
2. Travel GMT (True GMT or Flyer GMT)
- The 12-hour hand can be adjusted independently.
- Ideal for frequent travelers as it allows you to quickly adjust the local time without affecting your home time.
Beyond these basic classifications, there are variations in design and functionality:
- Single-Crown GMT: Uses a single crown to adjust all hands
- Dual-Crown GMT: Has two crowns, one for setting the time and another for the GMT hand
- GMT with a 24-hour bezel: Offers an additional visual reference for time zones
- GMT with a ceramic bezel: Provides durability and scratch resistance
Why You Might Want a GMT Watch
Frequent Travel
For those who often cross time zones, a GMT watch is indispensable. It allows you to keep track of both your home time and the local time effortlessly.
- Global Business: Professionals dealing with clients in different time zones benefit greatly from a GMT watch. It helps coordinate meetings and calls efficiently.
- Shift Work: For shift workers, a GMT watch can help manage work and personal schedules more effectively.
- Long-Distance Relationships: Staying connected with loved ones in different time zones is easier with a GMT watch.
Style and Functionality
- Sophistication: GMT watches often have a more complex design and are considered more sophisticated than standard watches.
- Versatility: Many GMT watches have a sporty yet elegant look, making them suitable for various occasions.
- Functionality: Beyond timekeeping, some GMT watches offer additional features like chronographs or compasses, adding to their utility.
What Are Some of the Best GMT Watches to Consider?
Do you want to wear your own GMT watch? Here are some of the best GMT watches that we recommend:
- Unique Feature: The iconic two-tone "Pepsi" or "Batman" bezel
- Characteristics: Highly legible, robust, and precise. It features a rotatable 24-hour bezel that allows tracking of a third time zone in addition to the local and home time.
2. Omega Seamaster Planet Ocean GMT
- Unique Feature: Helium escape valve for professional diving
- Characteristics: Water-resistant up to 600 meters, this watch combines Omega's renowned durability with a GMT function. These are great for swimmers, snorkelers, and scuba divers.
3. Tudor Black Bay GMT
- Unique Feature: Vintage-inspired design with a modern movement
- Characteristics: Its "Pepsi" bezel offers a 70-hour power reserve and is a more affordable alternative to its Rolex counterpart.
4. Breitling Avenger II GMT
- Unique Feature: Bold and rugged design with military-grade specs
- Characteristics: A large, easy-to-read dial with a 24-hour scale, this watch is built for adventure, offering shock resistance and water resistance up to 300 meters.
5. Grand Seiko SBGJ201
- Unique Feature: High-beat movement at 36,000 vibrations per hour
- Characteristics: With exquisite finishing and precision, the Grand Seiko GMT combines traditional Japanese craftsmanship with modern technology.
6. TAG Heuer Aquaracer GMT
- Unique Feature: Dual-tone blue and black ceramic bezel
- Characteristics: A versatile sports watch that’s water-resistant up to 300 meters. It has a bold design and reliable GMT functionality.
7. Jaeger-LeCoultre Polaris Geographic WT
- Unique Feature: World time function with an inner rotating bezel
- Characteristics: This watch offers a sophisticated combination of world time and GMT functions with a refined design. Suitable for casual and formal occasions.
- Unique Feature: Iconic cushion-shaped case with a crown-protecting bridge
- Characteristics: A large and robust watch with a GMT hand and a minimalist dial, combining Italian design with Swiss precision.
9. Bell & Ross BR V2-93 GMT
- Unique Feature: Aviation-inspired design with a vintage feel
- Characteristics: Has a clear, legible dial and rotating 24-hour bezel. It is ideal for those who love military-style watches with a modern twist.
10. Patek Philippe Aquanaut Travel Time
- Unique Feature: Dual-time zone mechanism with day/night indicators
- Characteristics: A luxury sports watch with a sleek, modern design, combining the practicality of a GMT function with Patek Philippe’s signature elegance and craftsmanship.
Conclusion
The world never sleeps. The GMT watch is your constant companion, enabling accurate timekeeping wherever you are. It remains a timeless classic. Its appeal lies not only in its functionality but also in its aesthetics. The GMT watch is a reminder that while the world may be vast and complex, with the right tool, we can conquer any distance, both physical and temporal.
