The Robust and Tool-like Isotope Hydrium California Limited Edition
A compelling diver showcasing Roman and Arabic numerals.
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Over 70% of our precious Earth is covered in water, and huge areas of it have not yet been fully explored. It’s very likely we’ll never manage to discover all the far corners of the oceans, as they are one of the most challenging environments mankind can face. The main issue is pressure, which increases by 1 bar (or 14.5 PSI) every ten meters down. At 60 meters below the surface, the pressure is already seven times the air pressure we face on land. That hasn’t deterred us from diving into the deep and finding out as much as possible about underwater life as we can. Professional and recreational diving has long relied on mechanical watches for timing a descent and, more importantly, the ascent to avoid running into issues such as decompression sickness. And even with dives now being timed by computer instruments, the appeal of a mechanical dive watch has stuck. The robust nature of a dive watch is the reason we still see so many of them, ranging from very affordable to rather expensive and even nigh-on impossible to get. One of the more recent and captivating dive watches, and one at a relatively fair price, is the Isotope Hydrium California. So please put on your scuba suit, and let’s dive straight in!
Starting with its exterior, the Hydrium California has a case that stands out from the masses. Sure, there will be similarities here and there, perhaps, but that’s pretty much a given within the dive watch segment. You need certain features in order to make it a proper diver, and Isotope follows suit. Nevertheless, the look and feel are very nice, with a micro-blasted matte finish for the 40mm by 14.9mm stainless steel case.
It has a stout middle case with well-rounded lugs and a very prominent bezel on top. This rotates one way only (counter-clockwise, obviously) and is fitted with a glossy black insert with a beige diving scale. The zero marker is Isotope’s signature Lacrima (teardrop) logo, tying it in with previous collections such as the Old Radium Bronze Tobacco Pilot’s Watch. This is also found on the crown and the caseback. The screw-down crown has two subtle guards that protrude from the caseband, and the water-resistance rating is 300m.
Even though the case has quite an original design, it’s the dial that won me over. The Hydrium Seconde/Seconde/ before it, as well as the Hydrium x Blink, already showcased Isotope’s creative and colourful side, but this one takes it in a new direction. Out is the whimsical approach, and in comes a more tool-like dial. The coarsely grained matte black dial shows a mix of beige Roman and Arabic numerals, resulting in a so-called California dial (hence the name). The indices are raised and finished with Super-LumiNova, as are the i-shaped hour and minute hands. The central seconds hand has a small plot of lume on its tip. The only other break in the dial’s muted colour scheme is the white minute track on the outer edge, the red *HydriumCA print, the white print for the logo, the fact it’s automatic and the watch’s water-resistance of 1,000 feet or 300 meters.
Underneath the see-through caseback is a Landeron 24 automatic movement. We don’t see this one very often, so it’s a nice break from the Sellita, Soprod or STP alternatives. At heart, it’s based on the architecture of the ETA 2824-2 and will indicate hours, minutes, seconds and the date. For the Hydrium, however, Isotope has decided to drop the date display at 3 o’clock in order to get a clean time-only dial. The movement itself runs at a rate of 28,800vph and has a maximum power reserve of 40 hours. The finishing is quite nice, with Geneva striping, perlage and blued screws. It is said to be regulated to run within +/- 12 seconds per day, but when I had the watch it ran well within those parameters, and I didn’t notice any significant advancements or delays in its timekeeping.
Isotope supplies the Hydrium California with a black tropic-style FKM rubber strap as standard, but at a small premium, you can opt for the tan suede leather strap instead. And if you’re really looking to splurge, you can have both. Speaking of which, the base price for the Hydrium California L.E., which is limited to 200 pieces, is GBP 900. This equates to just over EUR 1,000 before taxes. This goes up depending on the strap options you have selected. Both straps, plus additional colours and styles, are also sold separately, so you don’t have to make a decision right away.
During my time with the watch, I sort of fell in love with it. It sits well on the wrist despite the rather chunky build. This ‘chunky’ sensation is mainly due to the height, as the diameter of 40mm is very reasonable for a robust 300m diver. Nevertheless, you feel it on the wrist, but comfortably. The fit and finish are very nice, the design is quite original and the California dial is quite fun. So, all in all, it’s a compelling dive watch at a relatively affordable price!
For more information or to put in an order, please visit IsotopeWatches.com.
2 responses
Thank you for showing the side view of the watch, it really helps getting a better picture. I wish every article had one!
By the way pressure at 60 m below the surface is 7 times the pressure at sea level (twice at 10 m, 3 times at 20 m, etc).
You’re welcome, and we’ve updated the intro 😉