Some watches stand out immediately when you see them. The Isotope HydriumX “Will Return” is that kind of watch. It’s bold, it’s colorful, and it commands your attention. But it wasn’t the first model of the Hydrium series that I noticed. It was the Hydrium Burnt Tangerine that first caught my eye. It’s essentially the same watch as the HydriumX “Will Return”, but it features a dial in a nice shade of orange. But it was more than that. I loved the overall aesthetic of the Hydrium. It’s why I was very happy to try out the colorful HydriumX “Will Return” and the stealthy Hydrium Blue Night.

I’m all for conceptual watches that play with a familiar narrative, and that’s exactly what Isotope Watches has created with the Hydrium series. Isotope is a young brand founded by Portuguese native and London resident José Miranda. The brand was founded in 2016 and draws inspiration from a wide range of different influences for its designs, from car racing to Gérald Genta to Max Bill and Bauhaus. I love that Miranda is inspired by so many different things. The biggest challenge, however, is making sure that all the influences add up to recognizable and well-designed watches.

The Isotope Hydrium series

While I noticed Isotope’s earlier watches, there was never a model that blew me away. Don’t get me wrong; they are well-designed watches with interesting takes on existing ideas. A great example is the Goutte D’Eau that Rob wrote about last year. But as you will undoubtedly understand, a watch needs to “click” with you, for lack of a better word. That happened when I saw the Hydrium Burnt Tangerine. The overall vibe of the design is a traditional high-visibility dive watch with a minimalist concept. I love the idea of playing with something that feels familiar while simultaneously putting a new spin on it. And that’s what the minimalist Hydrium Burnt Tangerine does.

But it doesn’t end there. Not long after seeing the Burnt Tangerine, Lex and I were tipped by our friend Chip Yuen from Dutch brand Aevig Watches to check out the HydriumX “Will Return”. The first thing that stands out is the colors. But the overall design is a lot more traditional in its execution of elements. That’s when I realized that Isotope was on to something special. And it’s why I was very happy to see the HydriumX “Will Return” and Hydrium Blue Night land on my desk. They were prototypes, and the final versions will have some changes. I will take you through all of them to get an idea.

The Inspiration for the Hydrium

The canvas for the Hydrium series is a 40mm micro-blasted stainless steel case and crown. The case looks raw in color but is actually nicely refined. It creates a very nice toned-down aesthetic that feels great to the touch. The modern case shape was inspired by the Streamline Moderne era of the 1930s. It was part of the Art Deco movement and was defined by curved shapes and long, horizontal lines. From day one, it’s been the inspiration for all the watch cases that Isotope has created. Overall, I love the case shape. As I said, it feels modern, and on top of that, it is very easy to wear.

At 40mm, it is the perfect size for a wide range of wrists. The case itself measures 12.9mm in height, but with the double domed sapphire, it comes in at 14.9mm. While this sounds like quite a significant number, I never considered it an issue with the watch on my wrist. With a 48mm lug-to-lug and a 22mm lug width, the case of the Hydrium series is one of the most comfortable cases I have come across recently that also looks very nice. Additionally, it is water-resistant to 300 meters. As you can see, the prototype still has a helium escape valve, an element that will not be part of the final production model. Overall, I have to give Isotope compliments for creating a very nice modern case design that feels sturdy and is very comfortable on the wrist.

The Isotope HydriumX “Will Return”

The case of the Hydrium series serves as a canvas for various, distinct concepts and inspiration. The first of the two watches that I enjoyed reviewing was the Isotope HydriumX “Will Return.” The watch takes inspiration from the iconic “Will Return” clock door sign that tells when a shop will be open again. It’s a genuinely fun play on this clock that we probably all know, usually indicating at what time a shop will re-open after lunch. Essentially, Isotope has created a colorful red, white, black, and blue version of the iconic clock for the wrist.

The Isotope HydriumX “Will Return” has a fully lumed white dial with black printed details. It features large black hour numerals, a black minute track, the logo at 12 o’clock, and the model name and other info at 6 o’clock. I love that the font of the Arabic numerals is modern and perfectly legible. The handset is modeled after the water droplet-shaped hands from the door-sign clock. They almost have a similar shape to the teardrop motif or “Lacrima” the brand uses for many of its watches. But I’ll get to that with the Blue Night.

The different design elements

If you look closely, you will see a very small seconds hand. It turns very subtly, but it’s a great design choice because it does not interfere with the hour and minute hands. They are the most important, after all, because they’re the only two hands that the shop clock has. The subtle rotation of that tiny hand also serves as an indication that your watch is running.

The bezel insert has a fantastic bright blue color and is made of sapphire. It gives the 120-click unidirectional bezel a shiny presence that contrasts well with the matte appearance of the case. The bezel insert features a small red “Lacrima”, or teardrop shape, as the only marker. As there is no scale on the insert, it makes sense to position the bezel so the red indicator is located at 12 o’clock.

Isotope will equip the final version of the HydriumX “Will Return” with the automatic Landeron 24 caliber. Landeron is well-known amongst watch fans as a historical name. In 2018, Depa Swiss Movements Company started producing mechanical movements under the Landeron name. With this movement, Isotope will replace the Miyota 9039 used for previous versions of the watch. The Landeron movement operates at 28,800vph and has 25 jewels and a 40-hour power reserve. On a related note, the knurled screw-down crown is easy to grip, and it has a very sturdy and high-quality feel when setting the time.

The incredible lume fest

But we have to talk about the fully lumed dial because it adds another dimension to an already fun and vibrant design. In darker lighting conditions, the Super-LumiNova-smothered dial lights up brightly. I loved activating the lume at night, only to find out that it lights up perfectly and stays lit for quite a long time. As some of you will know, I have a soft spot for fully lumed dials, so this HydriumX “Will Return” awakened the little boy in me. As a result, I spent several nights playing with the lume, and it was impressive and fun. The watch comes on a 22mm tropical-style rubber strap that is very comfortable, and it makes wearing the watch an absolute joy.

If the prototype’s lume was not already impressive enough, Isotope has indicated that the lume on the production models will be even brighter and better. If you’ve ordered one, I can promise you that it will be a lot of fun. Unfortunately, during the time we had the watch in our office, all 100 pieces that Isotope will be producing of the watch have sold out. It means that you won’t be able to get one by the time you read this, unfortunately. I am one who missed out on buying one of them, which is a shame, as I really loved wearing the watch. With a special discount code, this watch was £450, but they have all flown the nest. It is no wonder because this is a watch that brings a lot of value for money. On top of that, it is tons of fun without being gimmicky.

The Isotope Hydrium Blue Night

The second of the two watches I got to review is the more serious-looking Isotope Hydrium Blue Night. It features the same case and black rubber tropical-style strap as the “Will Return”, but that’s where the similarities end. The Hydrium Blue Night has more in common with the Hydrium Burnt Tangerine that I talked about earlier. The central idea behind the Hydrium Blue Night was a dress watch that one could also use as a tool. It’s a concept captured perfectly by the design and the colors. The watch looks more like a tool watch because of its case, but the stylish presence ensures you could wear it in more formal situations as well.

Though you could take the Hydrium Blue Night diving, it’s not a watch that was created for that. Far from it; it was intended as a pure statement of style, and I love that about it. The watch features a beautiful, deep black enamel dial that features Isotope’s “Lacrima” design. The teardrop shape is inspired by the famous kitchen clock designs that Max Bill created for Junghans in the 1950s. It’s a detail that I adore because I happen to love these classic creations. Furthermore, the dial features a subtle white minute track with the indexes filled with Super-LumiNova.

A classy dark presence

Above the shiny black dial hovers a set of three dark flame-blued hands. The hour and minute hands are filled with Super-LumiNova as well. They ensure you can read the time in darker lighting conditions. But while that is practical, it’s the rather impractical but intriguing color combination of dark blue and black that gives the watch its presence. It’s the same color combination we see on the sapphire bezel with its dark blue “Lacrima”. Combined with the black strap, it creates a very stylish watch that I loved wearing.

If you turn the watch around, you will find a solid screw-down case back, unlike the display case back of the “Will Return” model. The engraving features sharks, an anchor, an old diver’s helmet, and a ship’s wheel, emphasizing its diver’s roots. The overall feel and execution of the case and case back are solid, and you can tell they are made with an eye for quality. I have to say, I was impressed by the quality of both watches, which is evident in many details, including the deep embossing.

Constant improvements

More proof of José Miranda’s eye for detail and willingness to improve is that both watches will be equipped with a black quick-release FKM rubber strap with a signed micro-blasted steel buckle. The straps on the prototypes did not feature the quick-release system yet. Another detail that will be improved is that the curved sapphire crystal will be equipped with an AR-coating. It will be helpful because the prototype was like a mirror, as you can see in the picture above. Say hi to Bert, Fratello’s in-house photographer!

Overall, I love this Hydrium Blue Night a lot. It is a stylish statement that would fit perfectly into my world of black outfits. On top of that, I think it’s great to see the brand is constantly improving details to produce better watches. Eventually, that will make the Hydrium Blue Night an even better watch. At the moment of writing this review, the watch is still available for sale. Just as with the “Will Return”, Isotope will produce a limited run of 100 pieces available for a special discount price of £450. After that, the price will be £563, so be quick if you want one.

Final thoughts

After wearing both watches for several days, I was impressed by the clever designs, the level of quality, and the overall comfort of the Hydrium series. For their discounted £450 price, these watches offer great value for money. Even for the normal retail price of £563, either one would be a great buy. When it comes to my preference of the two, I have to say, the HydriumX “Will Return” really stole my heart. It is the one colorful watch that I would love to add to my collection. It is a joy to wear, the lume is spectacular, and the overall quality deserves nothing but praise.

While I also love the Hydrium Blue Night from a conceptual point of view, and it would also suit my usual choice of clothing better, it would be one of several black watches that I own. That makes the HydriumX “Will Return” the right pick for me. But it doesn’t take anything away from the impressive achievement that Isotope managed to pull off with these two watches. Hopefully, we will see a lot more of them in the future, including a return of the “Will Return”. With a name like that, Isotope has to do it!

Let us know what you think of these two Hydrium models in the comments, and find out more about Isotope on the brand’s official website.

Watch specifications

HydriumX "Will Return" and Hydrium Blue Night
HydriumX "Will Return" - white dial filled with Super-LumiNova, Hydrium Blue Night - black enamel dial
Case Material
Micro-blasted case 316L stainless steel
Case Dimensions
Diameter - 40mm, lug-to-lug - 48mm, lug width - 22mm, height - 14.9mm
Sapphire crystal
Case Back
HydriumX "Will Return" - display case back, Hydrium Blue Night - screw down close case back
Landeron Caliber 24, 28,800vph, 25 jewels, 40 hour power reserve
Water Resistance
300 meters
22mm Quick-release FKM strap with signed micro-blasted Steel Buckle
Time - hours, minutes, seconds
Special pre-order price £450/€538, after that normal price £563/€675