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Despite offering a rather distinct and unusual appearance, the Isotope Hydrium series has ultimately proven to be a rather versatile platform, and in the years since making its first appearance, the Hydrium case profile has lent itself to a variety of different collaborations and limited-edition models. As its latest new release of 2023, Isotope has teamed up with the irreverent Paris-based watch customizer Seconde/Seconde/ to create a limited-edition version of its Hydrium dive watch. While the original idea for the collaboration was to create a piece that celebrates Isotope’s new logo and the brand’s 7th anniversary, Seconde/Seconde/ thought it would be more appropriate to design a watch that celebrates the death of Isotope’s previous logo, and the new Isotope Hydrium Seconde/Seconde/ is designed to be a memento mori watch that specifically does not incorporate a skull into its design.
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From an external case and construction perspective, the new Isotope Hydrium Seconde/Seconde/ watch is more-or-less identical to previous Hydrium and HydriumX models, which means that it has the same 40mm micro-blasted stainless steel case that measures 48mm lug-to-lug by 14.9mm thick, which includes the double domed anti-reflective sapphire crystal that sticks up about 2mm above the rim of the bezel. Similarly, the case features 22mm lugs, and fitted to them is a black leather strap with bright green contrast stitching that features integrated quick-release spring bars and a signed micro-blasted stainless steel pin buckle.
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Just like other models from the Hydrium collection, a signed screw-down crown at 3 o’clock works with a sapphire screw-down caseback to help create 300 meters of water resistance, while the 120-click unidirectional rotating timing bezel is fitted with a sapphire crystal insert. Additionally, on the new Seconde/Seconde/ edition, the insert is black with a single bright green lacrima (teardrop shape) to denote the zero marker. Aside from the color of the insert, the new Isotope Hydrium Seconde/Seconde/ promises to deliver much of the same on-wrist experience as previous Hydrium and HydriumX models, and it offers a fun and almost cartoon-like rendition of the classic dive watch format.
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The dial of the Isotope Hydrium Seconde/Seconde/ feature a matte black surface with a raised lacrima in the center of the dial and a railroad-style minute track printed along the periphery in white with small bright green blocks to denote the hour markers. At the top of the dial is Isotope’s original logo, although it has been overhauled by Seconde/Seconde/ and given a number of bright green updates. The actual letters of the Isotope name have been rearranged to spell “OTOPSIE” (autopsy), with green arrows pointing to where the letters would go if the logo were to be printed normally.
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At the very top of the dial next to Isotope’s emblem is a small “+ S” in bright green that mirrors the font used for the Seconde/Seconde/ logo, and this serves as a subtle way to signify the collaboration. Similarly, while the hour and minute hand appear in Isotope’s classic i-shaped format, the bright green seconds hand has a shape that mirrors the appearance of a failing heartbeat on an ECG machine. Additionally, the hour markers, hands, and lacrima on the bezel insert are all finished with green emission Super-LumiNova, and the entire seconds hand is luminous for a rather striking and unusual display in the dark.
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Just like all of Isotope’s traditional three-handed models, the new Hydrium Seconde/Seconde/ is powered by the Swiss Landeron 24 automatic movement, which follows the same core design as the ETA 2824 or Sellita SW200 and therefore runs at a frequency of 28,800vph (4 Hz) with a power reserve of approximately 40 hours. Better decorated than its ETA or Sellita equivalents with perlage and Geneva stripes, the Landeron 24 is also less frequently used than its better-known counterparts, although it offers the same proven architecture and is accompanied by an accuracy rating of +/- 12 seconds per day.
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Like most of Isotope’s watches, the new Hydrium Seconde/Seconde/ will be produced as a limited edition, and for this particular collaboration, only 50 examples will be produced, with each one featuring its unique number engraved upon the rim of its caseback. Since this new collaboration watch has an entirely custom seconds hand, it is priced in line with the more premium models from the greater Hydrium collection, and the new Isotope Hydrium Seconde/Seconde/ is accompanied by an official retail price of £900 GBP (or about $1,110 USD, at the time of writing). Much like the vintage watches fitted with fun and quirky seconds hands produced by the Paris-based customizer, the new Isotope Hydrium Seconde/Seconde/ offers a witty and irreverent take on a familiar fan-favorite design, while simultaneously marking the official retirement of Isotope’s original logo. For more information on the Seconde/Seconde/ watch, please visit the brand’s website.