NTH 500M Devil Ray – GMT or Not GMT?

NTH 500M Devil Ray – GMT or Not GMT?

7 min read
Richard Brown





Richard Brown





When I interviewed Chris Vail, the founder of NTH, for our YouTube channel, he predicted that 2023 would be the year of the GMT. Why? In 2022, Miyota introduced a cost-effective GMT movement, their Calibre 9075, which allowed several brands to develop a reasonably priced GMT watch for the first time. Of course, GMTs are not new, far from it, but the ready availability of more good mid-range movements cannot be underestimated.

NTH Devil Ray Non-GMTNTH Devil Ray GMT
NTH Devil Ray Non GMTNTH Devil Ray GMT

NTH Devil Ray GMT VS NON GMT - Credit WatchGecko

At WatchGecko, we have a meaningful collaborative relationship with NTH. They are a boutique watch brand from Philadelphia, USA, specialising in capable steel tool watches. Their portfolio combines unique designs and models with a distinct "nod" to some more prominent brands. One of our NTH/WatchGecko collaboration ranges is the popular 1970s-inspired cushion case DevilRay. The standard non-GMT version of this watch is very much in the vein of classic dive watches from an era where SCUBA diving was relatively new and equipment far less sophisticated than it is today. A time when an ultra-reliable dive watch was a lifesaver, not a fashion accessory.

I have always been a fan of the DevilRay, primarily because I love 1960s and 1970s dive watches. The name of this model reminds me of glorious snorkelling days on Marisah Island in Oman when, after work, we used to take a Land Rover down to the waterfront and dive at a respectful distance from Bluespotted Ribbontail rays. Then, later, dry off on the beach, watching Manta Rays rise from the ocean floor and leap from the air above the water. There is something beyond sub-aquatic regarding rays. Truly creatures from another world, what better inspiration for a serious dive watch?

With these romantic images in mind, it was an apt moment to take home two DevilRays and see which I would eventually pick as a favourite. I had a non-GMT white dial and a GMT with a light blue one, both fitted to the standard issue NTH steel bracelet. No diving would be involved in the test, although with the October flooding in Derbyshire, it didn't feel like crushing water depths were far away.

NTH Devil Ray GMTNTH DevilRay GMT - Credit WatchGecko

Dive into the Devil Ray Range

At WatchGecko, we have twenty-seven variants of the Devil Ray for sale. Each one offers a different dial colour, complication or strap alternative. However, they all have a very distinct common DNA – that of a serious 500m dive watch drawing inspiration from classic watches which defined underwater exploration in the 1960s and 70s. All Devil Rays have a distinct cushion case which is wholly representative of the era. It stands high on the wrist at 14.5mm to maintain accurate styling, but this is a well-planned design characteristic. Due to the cushion case style, the watch is almost square with rounded edges. Diameter and lug-to-lug are similar measurements at 41mm and 46mm, respectively, allowing the watch to sit nicely on most wrists despite its immense water-resistant properties. 

NTH Devil Ray CasebackNTH DevilRay Caseback - Credit WatchGecko

The tactile screw-down crown is well recessed into the 316L case, negating the need for shoulder protection. The measurements and this crown design allow for a beautifully symmetrical case.

Hour markers across the range are bold and hands have a design theme with squat, purposeful hour hands and bright orange minute hands to reflect professional dive heritage. Some models have rehauts raised for a more 3D and striking look, but if you like a bit more real estate on your dial, then several models have vertical rehauts for a larger looking watch face.

A common element on all Devil Rays is the double-ring bezel. This unit permits both elapsed timing and rudimentary dual-time zone capability. The saw-tooth edge offers superior grip and striking looks.


NTH Devil RayNTH White DevilRay - Credit WatchGecko

The two Devil Rays I selected look very different. Despite the common design characteristics highlighted above, they have fundamentally contrasting appearances. The white dial non-GMT is a mono-tone steel design offset with three small bright orange elements. The chalk-white dial dominates, precision split with a printed cross-hair. Raised white hour batons are well highlighted so as not to merge into the dial and look protected as they slot into a prominently sloping grey rehaut. The hands are white with the hour and seconds having bold gloss black outlines and the hour being highlighted in orange. The seconds hand also has an orange point. The visual upshot of the overall design is superb legibility through the sapphire crystal combined with the lack of reflection you associate with a white dial watch. All time-keeping elements are deep-filled with X1 Super-LumiNova, for exceptional legibility in low-light conditions.

The twin-function 120-click bezel is all stainless steel with fully luminous numerals and, just when you thought the watch could not glow any more, the NTH engraved on the crown also glows blue. At night, this watch is a gem!

NTH Devil Ray LumeNTH Devil Ray Lume

Turn the DevilRay over and you are treated to an engraved ray with swirling water around it. This stylised image is the logo of the DevilRay and appears on some of the watch dials, but not on this more minimalist white model.

Behind the case back embossed ray beats a reliable NH38 no date movement which beats at 21,600 vph and has a 41-hour power reserve. This is a true non-date movement and, therefore has no phantom date crown position.

The watch came on the standard three link NTH bracelet with a double push button release and flip lock safety. Unlike an Oyster bracelet, NTH designs their links to meet at a slight V-shaped angle which gives the watch a dramatic look. The centre link is also deeply cut with three grooves and polished. The whole package of the watch head and bracelet match well.


NTH Devil Ray GMTNTH Devil Ray GMT - Credit WatchGecko

The Blue dial GMT I also tested was in many ways superficially externally similar to the white dial model. Other than the GMT function, the principal differences were a light blue dial, offset NTH and Devil Ray logos on the dial, a vertical mirror finish, rehaut and a two-tone bezel.  

This model is powered by the NH34A GMT movement which operates at the same vph as the NH38 and delivers identical power reserve. This is also a relatively new movement released only in the Summer of 2022. This is an "office" GMT but at the price point of the watch it will meet most traveller's needs unless they are a purist. The bezel's 01-12 outer ring works particularly well with this model.

The dial of this DevilRay was more fashionable thanks to the blue and arguably a more significant statement. The GMT hand stalk was also the same colour as the dial, with just the short arrow pointer in orange. It was very different to the large red 4th hands on some watches however, despite the subtlety, it delivered the performance I needed.

So which did I prefer?

NTH Devil Ray Non-GMTNTH Devil Ray GMT

If I had to choose, which was tough, the model I preferred was the white dial non-GMT as I have so many GMT watches I struggled to fall in love with another. However, if you are in the market for such a watch with exceptional underwater capability, you'd be pushed to find a better model at this price point than the DevilRay GMT.

When I held the 2 watches together, something compellingly clinical and functional about the non-GMT model resonated on a different level with me. It's like this watch isn't trying to be anything other than it is, a professional 500-meter dive watch with exceptional legibility which allows me to look back to the formative years of SCUBA diving.

For this test, I transferred both watches to a ZULUDIVER Padded Tropical Rubber Watch Strap (MkII) in black. There is absolutely nothing wrong with the steel bracelets supplied with both watches; it is just that I am not the biggest bracelet fan, and this was a personal test, so I set out to find an alternate strap that looked great, and I could quickly swap on to both watch heads. The black ZD Vintage Tropical was perfect; that is why you see it in the out-and-about photographs I took of the watches and one of the studio shots.

NTH/WatchGecko DevilRay GMT and Non-GMT Technical Specifications

  • Brand: NTH with design contribution from WatchGecko
  • Model: DevilRay GMT and Non-GMT
  • Price: From £495 to £575 depending on spec and strap choice
  • Material: Stainless Steel
  • Movement: NH38 or NH34A
  • Water resistance: 500m
  • Crystal: Domed sapphire crystal with AR coating
  • Dial: White and Light Blue on test
  • Size: 41mm diameter, 46 mm lug-to-lug, 14.5mm thick, 22mm lug
  • When the reviewer would personally wear it: As a sports watch for any occasion or when involved in dedicated water activities. At 500m water resistance it will never fail me. Also maybe after I have watched the 1977 movie The Deep.
  • A friend we’d recommend it to first: Someone who wants a dive watch that’s just a bit different. To someone who wants to spend around £500 and stay a world away from the 300m models which are £5000.
  • Best characteristics of the watch: 1970s styling and genuine dive spec capability.
  • The worst characteristics of the watch: 1970s styling! You’ll either love it or hate it.

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Richard Brown

About the Author: Richard Brown

I truly believe one of the best partners in exploration and adventure is a fine watch. Over 30 years of collecting, my fascination with the technical capabilities of both vintage and modern timepieces has never abated and it is a privilege to be able to share this passion through writing.

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