Posted on April 10 2020
The purpose of a watch is to tell the time. It sounds simple. Just tell the time. But, this basic concept has kept challenging watchmakers for two centuries. There has always been the need for innovation as users have found new environments in which to wear their watches.
Indeed, the popularity of the wristwatch itself is traced back to the first world war, when soldiers, out of necessity, began strapping pocket watches to their wrists. In a similar manner, the birth of aviation meant a need for large clear watches with the ability to wind and set the time whilst wearing gloves. Watch wearers will always find ways to push their watches to the limit. Historically, we’ve seen these developments as Navy’s demanded waterproof watches, pilots needed displays with multiple time zones and astronauts continued this trend for increased functionality with their own unique requests.
From the beginning of watchmaking, there has been one very obvious and very simple challenge.
How to tell the time in the dark.
Initially, the solution was to paint a radioactive substance, Radium, on to the hands and dial. The downside was the death of the workers, usually working-class women, who had to handle this on a daily basis. When Radium was finally banned in the 1960’s it was replaced by the much less radioactive Tritium. This, in turn, was replaced by the photoluminescent material we’re most familiar with now, Super-luminova and its rivals.
As good as these modern, safe lumes are, they do have their limitations. Specifically, they need to be charged by light. Worn through the day, they absorb light and then re-emit it during the night. So they do require that initial exposure to light and the subsequent glow that they produce does gradually weaken. Several hours later and it’s exhausted.
Swiss company MB-Microtec pioneered a solution. A modern, safe version of Tritium.
Tritium works in watches because it emits electrons through beta decay. When these electrons interact with a phosphorous material fluorescent light is created that can last decades.
The innovation is that MB-Microtec house the Tritium in a glass tube.
The glass is lined with phosphorescent material and then filled with gaseous tritium. This is known as Gaseous Tritium Light Source or GTLS. They are small, gas-filled tubes that produce a constant light for between 10 and 25 years. No charging, no dimming, and importantly no health hazards - the radioactive material is hermetically sealed. They produce these tubes with a T25 or T100 rating.
There are a number of brands that have really made the use of Tritium tubes their USP. Luminox and Traser spring to mind. With both of these companies, they began with, and still have at their core, a range of black military-style watches. They’re great - I have a Luminox 3000 series watch that I still wear regularly, but they’re the style of watch that comes up first when you Google GTLS. We are including both on this list, but we’re also going to make an effort to show you some of the watches that use GTLS in other styles. Watches that provide that supreme illumination but without the military aesthetics.
Where better to start our list than with the original. Traser is the brand founded by MB-Microtec, the inventors of GTLS. Initially, the brand supplied watches to the US military, producing 300,000 of its inaugural model, the P6500 Type 6. Swiss-based, the manufacturer has maintained that strong military heritage and to many that aesthetic will be the first they think of when discussing tritium watches.
Here I'd like to offer a slightly different style watch from the brand. Something unlike the black polymer style you may be familiar with. Still military in character, this watch has an aviation-style. Instead of a black dial and casing, we have an ivory dial in stainless steel.
The T5 Aviator Jungmeister features the tritium as expected, but mixes that with a more stylish profile. Despite quite a lot going on, the dial, with a sub-dial at six o’clock, doesn’t overwhelm. There’s still a clean look, ideal on a watch that values legibility and round the clock illumination.
At 46mm it’s a relatively large watch, and bear in mind there are pushers adding to that diameter too.
Traser T5 Aviator Jungmeister - 100190
Several years ago while browsing the watch forums I came across a wrist shot featuring a brand that was new to me. The watch in question was a Reactor Trident and I immediately ordered my own. It quickly became my go-to watch when I had a weekend where I planned to wear my watch at all times. This thing was bulletproof and was on my wrist for subsequent camping trips and festivals.
Less than twenty years old, this US company set out to create tough watches for action sports, often going far beyond what other brands would consider tough wearing. An example is their screw-down crown system that remains water-proof even when unscrewed. Another is their ‘Never Dark’ line. Watches that use Tritium tubes and Super-Luminova to get the best of each.
The Trident 2 has this feature and others such as a bolted-on bracelet, heavy-duty case back and substantial crown guards. It’s not a slim or light piece. It’s heavy and has bold styling. In many ways, it’s exactly the type of watch to make the most of GTLS technology. The tubes are on the hands and the 12, 3, 6 and 9 makers, with Super-Luminova on the hand tips and numbers.
Reactor Trident 2 50001
Luminox was created around GTLS technology when in 1989 Barry Cohen first came across this form of illumination. Along with a friend he formed Luminox, taking the name from the Latin for ‘light’ and ‘night’. Within a couple of years, they’d created a watch to be worn by the Navy Seals and the brand quickly gained industry recognition - read more here.
The company has added numerous lines to its range, but those nearest to the early Navy Seals watches are the most recognisably Luminox. I have a now-discontinued 3000 series Luminox and it ticks all the boxes of those early watches. A black polycarbonate case with a rubber strap and a bright orange dial with the tritium tube illumination.
In the spirit of highlighting watches that you may have missed, I've decided to choose a Luminox design that is far removed from the models that made the brands name.
The Atacama is a mid-priced all stainless steel automatic watch, paradoxically named as both a field and urban watch. The appeal is that it has a distinct styling that is at once recognisable as a field watch - reminiscent of say the Hamilton Khaki, but it also has a business casual design. This would work fine with a more formal dress.
Despite having the tritium tubes on both the hand and all the hour markings, the general feel isn’t that of a sports or military watch. It’s functional but in an understated way that doesn't diminish the design.
But this Swiss-made piece, with a Swiss mechanical movement, is still a reasonably chunky watch. It’s 44mm in diameter with a 24mm stainless steel bracelet.
Luminox Atacama Field Automatic, Urban Adventure - 1902
MWC stands for Military Watch Company. As Authorised Dealers, I'm a little biased towards this Swiss brand. They’re primarily known for producing classic military watches, from the British Army G10 to their remakes of US watches from the Vietnam era.
The Depthmaster is a more recent offering and part of their extensive Divers range. This particular variant is at the top of the specs they produce. It has a massive 1000M water resistance and a helium escape valve, the type used on watches provided to saturation divers - see more here.
The case is thick and heavy. The depth is 18mm and the width 44mm. Like most MWC watches this model is delivered with an easily replaceable canvas Nato strap and like all their automatics, is powered by Seiko’s NH35A movement. The ceramic bezel is a nice touch, as is the neat date window at 4 o’clock.
MWC Depthmaster - 100AT/1224/SS/SL/A
Where MWC made their business the production of military watches, so Deep Blue chose Divers watches as their niche. Specifically, they made water resistance the centre of their ethos. Their mission is to provide watches that can withstand submersion from between 300M to 3000M. They attempt to do this while making use of the latest watchmaking technology, but without sacrificing their modern clean aesthetic.
You’ve heard it a thousand times. It’s what so many companies aim to achieve, a balance between form and function.
Measured against this, the Bronze T-100 is a success. It has the classic styling of a diving watch with high specifications. So there’s the bronze case that will develop a natural patina and a water resistance of 500M. There’s the thick, distressed leather strap and Tritium tubes on the hands, dial and bezel. This automatic is powered by Miyota’s reliable 9015 movement.
Deep Blue - Bronze CuSn6 Daynight T-100
UK brand Nite was created in 2003 when Roger Green sunk his life savings into his new venture. The first watches were released the following year and he was soon supplying Britain’s elite troops, the SAS.
By 2006 the company was using GTLS for its illumination, now a defining feature of the brand. Nite then embarked on its direct-to-customer sales strategy and now sells exclusively online through its own website.
The brand made a name producing rugged military-style watches in the vein of competing brands Luminox, MWC and Traser.
This Alpha model is a very well executed diver that includes just enough colour to keep things interesting, but without over complicating the design. This quartz watch is housed in a brushed steel case and matching bracelet. As expected there’s a sapphire crystal, blue ceramic bezel and screw-down crown. It utilises both blue and orange T100 tritium and at 42mm is more modestly sized than some of the other watches highlighted.
Nite - Alpha ALPHA208ST100BLUE
In Armourlite, we again have a company that has made military watch design the core of its business. As they state on their home page “we are an American company that makes the toughest and brightest tritium illuminated watches”.
The brand’s story is quite similar to some of the other companies featured here. A founder with previous watch industry experience establishing his own brand. For Armourlite this began initially on the back of his development of Armourglass - a toughened mineral crystal. From there he began to produce polycarbonate watches with T100 illumination.
Again I'm highlighting a watch from their range that isn’t typical of their offerings. The AL821, whilst military in origin, is more of a classic field watch.
Part of the Officer Series, this model is protected by a shatterproof Armourglass crystal. Apparently, that means the glass can withstand up to 6,000 Vickers - that’s a lot of pressure. Built out of 316L stainless steel and illuminated by both orange and green tritium markers the watch is powered by a Swiss Ronda 517 movement. There’s also a modest water resistance of 100 meters.
ArmourLite Officer Series AL821
Marathon watches can trace its history back to the founding of Weinsturm Watch in 1904. The company became Marathon in 1939 and since 1941 has been supplying timepieces to the military. The company is still a family-owned business, currently in the hands of its fourth generation.
The Navigator model is built to strict military specifications under MIL-PRF-46374G.
First developed by Marathon Watch Company in 1986 this watch was made originally as a request by the Kelley Air Force Base. The result is a tidy watch with the distinctive asymmetrical case of a Navigator style model.
The watch is housed in a lightweight fibre shell case that is sweat and shock-resistant. There’s a couple of colour variations with each watch having been made in Switzerland and powered by a Swiss ETA F06 quartz movement. Like most military watches it’s not over-sized and comes in at a modest 41mm.
Marathon Navigator - WW194001
I've mentioned Vostok a number of times on this blog. They’re an iconic brand. The company that became Vostok can be traced back to WWII and Russia’s involvement in the conflict.
At the tail end of 1941, one of the Moscow watch plants was evacuated, in 150 railway carriages, to Kazan in South-West Russia. From there the story goes, the equipment, workers and their families covered the final 100KM to the city of Chistopol in a convoy of three thousand carts pulled by horses.
By April 1942 the factory was up and running and producing its first items for the military. However, wristwatch production didn’t begin until after the end of the war. 1965 is really where the story gets interesting for watch fans. It was then that the Chistopol Watch Factory became the official supplier of watches for the Ministry of Defense of the Soviet Union.
In 2003 a joint venture between the Chistopol factory and Vilnius Koliz resulted in the launch of the Vostok-Europe brand. Then in 2009 collaboration between Vostok-Europe and Mb-microtec laid the foundation for a new line of watches with tritium tubes.
This particular model was created for the fifth anniversary of the World Record expedition that made it to bottom of the deepest cave in the world, also known as underground Everest.
It’s an eyecatching watch powered by Seiko automatic movement and has both a power reserve and a 24hr sub-dial. The large 48mm case is PVD coated and there’s a hardened mineral crystal.
Vostok Europe Expedition Everest Underground YN84-597A545
Smith and Wesson don’t have a strong heritage as a watch brand, but this model is impressive, if somewhat very similar to a Reactor.
My final watch has all the features that we’d expect. A chunky stainless steel case, a mineral crystal and a quartz movement. It has a busy dial that is military in inspiration and clear and legible. Overall it’s a nice watch that is getting increasingly difficult to find.
Smith & Wesson 357 Aviator