Tritium Illumination

Tell the time all the time

Being able to tell the time with ease in the dark is often overlooked in the process of buying a watch.

This ability however, of always being able to tell the time no matter what the conditions, is always highly valued in the day to day life of a watch.

This is the reason therefore why each and every Nite watch is fitted with tritium illumination - the very best form of watch illumination available.

Key Features

  • Tritium illumination is a completely safe and reliable form of illumination – the electron emitted by Tritium is so low in energy that it is unable to penetrate the human skin.

  • The Tritium illumination used in all Nite watches is supplied by mb-microtec of Switzerland – the original founders and market leaders of the technology.

  • The T rating relates to the total watch radiation content measured in millicuries. We offer both T25 and T100 rated watches.

  • Tritium illumination will provide a constant glow throughout the night unlike traditional illumination such as Superluminova which will fade in a number of hours.

  • Tritium illumination will provide a constant glow throughout the night unlike traditional illumination such as Superluminova which will fade in a number of hours.

  • Tritium illumination is completely self-powered and doesn’t require sunlight or any other form of external power to operate.


Tritium, also known as super heavy hydrogen, was first discovered by Ernest Rutherford, ML Oliphant and Paul Harteckin in 1934.

Tritium emits electrons through beta decay and when these electrons interact with a phosphorous material, a fluorescent light is created that can last up to 20 years.

When this Tritium powered illumination is sealed inside a glass tube, it is known as a GTLS (Gaseous Tritium Light Source) which is up to 100 timesbrighter over a long period than any comparable technology.

To produce a GTLS vial, glass is lined with phosphorescent material, then filled and pressurised by a machine with gaseous tritium and sliced into segments by a laser beam to be sealed hermetically.

Inside the vial, the electrons emitted by the tritium gas excites the phosphor to give off the cold continuous light. GTLS can be created in different colours, generally green is perceived by the human eye as the brightest colour.

Completely self-powered and providing a constant glow throughout the night, Tritium illumination technology has been trusted for decades by the emergency services, mountaineers, deep-sea divers and military personnel due to its unwavering reliability and performance in mission critical situations.

T25 VS T100

We offer both T25 and T100 rated Tritium watches. The T rating refers to the total watch radiation content which is measured in millicuries. All watches with a T25 rating contain up to 25mCi of radiation content and similarly, watches with a T100 rating contain above 25mCi and up to 100mCi. Whilst there are differences between the amount of mCi in the T25 and T100 models, the idea of “which is better” is simply a choice of preference and taste.


Second hand misses a few markers, but is precise on at least 80%. Accuracy is right-on for the week I've had the watch.

Charles Boyd 20/9/19

Easily one of the best-looking, most well-made, and all-around excellent products - watches or otherwise - I've ever purchased. Can't say enough good things about this Hawk.

Dylan Hayre 20/9/19

Good watch.

Antony Heath 19/9/19

Very easy to read at night which helps me keep track of mother's falls. Just a superior timepiece that will lend itself for dive & hunting outings!


I received a faulty watch but I'm willing to give another chance

GLENN 17/9/19

This is my second nite watch very pleased with purchase just what I was looking for

A B 16/9/19

Nice elegant design. Great blue tritium. You can opt to use stainless steel or rubber strap depending on your activity. Future upgrade? I think automatic movement will be great to have smooth movement of the seconds dial. Also hoping there will be an Alpha with 48mm body diameter.

Roel Bascon 13/9/19

Great looking men's watch. Very stylish. The tritium illumination is wonderful.

Lawrence Nader 13/9/19

It's slim, yes, but it's built like a beautiful tank! I liked it so much I bought another. The case is bowl-shaped which gives it a slim profile on the wrist but a very solid feel. The lume is extraordinary, again very smart, very gentile but with the full whack of T100 GTLS. The strap is far better than many leather straps I've had. Refined calfskin without stitched seams but shapes perfectly to the wrist and is very robustly constructed. All together a very well thought out watch, very considered in design and function and very very well engineered.

Thomas Glover 11/9/19

Beautiful watch

Thongsin Dhanasang 11/9/19

This is my second Nite Watch. Love the brand.

Paul Mullen 10/9/19

A great watch that will stand up to daily use with ease. This is a robust waterproof timepiece with a bezel and face that can be read at any time day or night with exceedingly clear illumination. A reassuringly well made strap and sapphire crystal glass provide additional secure use.

A happy customer 10/9/19

A watch that is no doubt well named and worthy of a nobleman. While quite large on the wrist, the ease of reading the face, combined with the slim case allows it to be worn with ease under any long-sleeved shirt, buttoned-down or with cufflinks. The tritium dial is superb, as per Nite standards.

A happy customer 10/9/19

The watch displays quality from the look and feel to the box it was packaged in. Very pleased witht the purchase and so far appears to keep accurate time. (only had it one week) The night illumination is just right. Would recommend this watch to anyone who has a small wrist as it's size looks right on the smaller wrist.

C Rickett 10/9/19

Excellent product - but I do miss not having the date on the watch.

Christopher Fisher 10/9/19

Beautiful watch, I thought it might be too big since I have thin wrists but the strap was smug and it looks great. The look and quality of the watch are excellent.

Neil Evett 9/9/19

Smart and casual

tony Line 9/9/19

Quite high quality. Love from Kyoto, Japan!

Hisashi Kurachi 8/9/19

A nice lite weight slimmer time piece sharing the same great qualities as it’s rugged counterparts. Visible and readable night or day a great complement to a shirt with or without a tie Stef

Mr BARR 5/9/19

Excellent product, easy to read both day and night, very happy with the 'Icon'

MR R A KEYSE 5/9/19

Now you know all about Tritium illumination

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