RESERVOIR Hydrosphere Blackfin Dive Watch
Starting from 5.400 €The RESERVOIR Hydrosphere Blackfin is a Swiss Made dive watch that upends the codes of the genre. True to the French house's obsession with measuring instruments, it transposes onto the wrist the aesthetic of early divers' air pressure gauges, with the time read off a single hand on the dial. Its satin-brushed 45 mm 316L steel case, unidirectional ceramic rotating bezel with double scale, helium escape valve and 250-metre water resistance make it a genuine diving instrument, not merely a style piece. Powered by a patented 124-part module grafted onto an ETA 2824-2 base, it targets divers and collectors seeking a genuinely different display.
RESERVOIR Hydrosphere Blackfin dive watch
RESERVOIR is a French house founded in 2017, building its entire Swiss Made production around a single idea: transposing the reading of measuring instruments onto the dial. Pressure gauges, fuel gauges, rev counters, these technical displays gave rise to an instantly recognisable horological language, built on a systematic triptych. Jumping hour on a disc, retrograde minute over 240 degrees and a power reserve indicator replace the classic pairing of hour and minute hands. A single hand sweeps the dial before snapping back to its starting point at the end of each hour.
The Hydrosphere is the underwater translation of this vocabulary. Launched in 2019, it borrows its graphic language from the air pressure gauges of early divers, dials the brand describes as the diver's first survival instruments. The Blackfin version, with its black dial and steel case, serves as the line's iconic piece, alongside the white-dialled Air Gauge and the blue-dialled Blue Hole. Two limited bronze series, The Greg Lecoeur Edition and the Hydrosphere Bronze x Revolution, rounded out the family before selling out.
François Moreau, the brand's founder, claims this line as the world's first retrograde dive watch, on condition that it remains a genuinely functional instrument underwater. The Blackfin lives up to that double demand, balancing horological styling with a fully capable diving tool.
Technical specifications RESERVOIR Hydrosphere Blackfin
- Brand: RESERVOIR
- Model: Hydrosphere Blackfin
- Reference: RSV03.HY/130-21.BF
- Indicative price: 5,400 €
- Movement: Swiss automatic
- Calibre: Patented module on ETA 2824-2 base
- Power reserve: 37h
- Diameter: 45 mm
- Thickness: 14.9 mm
- Water resistance: 250 m / 25 bar
- Materials: 316L stainless steel case, ceramic bezel,
- Crystal: Anti-reflective sapphire
- Dial: Black, white Super-LumiNova hour markers
- Strap: Brushed 316L steel with deployant clasp
- Warranty: 2 to 3 years after online registration
- Box contents: Watch, waterproof container box, additional rubber strap
The RESERVOIR Hydrosphere Blackfin dive watch
On the wrist, the Hydrosphere Blackfin immediately makes its presence felt. Its satin-brushed 316L stainless steel case measures 45 mm in diameter for 14.9 mm in thickness, unapologetic dimensions that live up to the instrument vocation claimed by the brand. The satin finish breaks up reflections and gives the piece the look of a tool rather than a jewel, in the spirit of the measuring devices that inspired it. The anti-reflective sapphire crystal protects a deep black dial, laid out like the face of a diving pressure gauge. Reading it takes a second to learn, then becomes obvious. The hour appears in a window topped by a magnifying lens, the minutes are shown by the single central hand sweeping across a wide arc before dropping back to zero, and a dedicated sector reports the energy remaining.
The white Super-LumiNova hour markers ensure legibility in dark water, while a running seconds indicator at the base of the hand rotates continuously to confirm at a glance that the movement is running correctly. This highly graphic dial architecture sets the Blackfin apart from every conventional diver. Yet it retains the reference points a diver expects: maximum contrast, generous numerals, a clear scale and no superfluous information. With its unidirectional ceramic rotating bezel, the watch remains above all a diving companion, both a technical showcase and a field instrument.
A retrograde display built for immersion
The heart of the Blackfin is a Swiss Made automatic mechanical movement, whose originality lies in the patented 124-part module grafted onto an ETA 2824-2 base. It drives the jumping hour window, the retrograde minute and the power reserve indicator, three complications combined to offer just a single hand on the dial. Beating at 28,800 vibrations per hour, the assembly delivers a 37-hour power reserve, to be monitored on its dedicated sector whenever the watch is left at rest. The rest of the construction follows purely subaquatic logic.
The unidirectional ceramic rotating bezel carries a double scale, designed to keep tracking dive time after the retrograde hand has snapped back to zero, an essential trick for this type of display. The screw-down crown, screwed steel caseback and helium escape valve accompany a 250-metre water resistance, or 25 bar, which places the Blackfin firmly among genuine divers' watches. On the wearability side, the brushed 316L steel bracelet is screwed to the case and fastens with a folded-blade deployant clasp fitted with an extension system, useful for fitting over a wetsuit. An additional black rubber strap is supplied, allowing the watch to be lightened for the water and returned to steel for everyday wear.
RESERVOIR Hydrosphere Blackfin dive watch: one hand, 250 metres
The RESERVOIR Hydrosphere Blackfin combines a satin-brushed 45 mm 316L steel case, a unidirectional ceramic rotating bezel with double scale, a helium escape valve and 250-metre water resistance. Its black dial, inspired by diving pressure gauges, combines a jumping hour under a magnifying lens, a retrograde minute and a power reserve indicator, with white Super-LumiNova hour markers under an anti-reflective sapphire crystal. The Swiss Made automatic movement pairs a patented 124-part module with an ETA 2824-2 base, beating at 28,800 vibrations per hour for 37 hours of autonomy. A steel bracelet with extension system, an additional rubber strap and a waterproof container complete the delivery.
Movement
The Blackfin is powered by a Swiss Made automatic mechanical movement, whose entire personality rests on the patented 124-part module mounted on an ETA 2824-2 base. This proprietary architecture drives the jumping hour window, the retrograde minute and the power reserve indicator, a reading entrusted to a single hand. Beating at 28,800 vibrations per hour, the calibre delivers a 37-hour power reserve. A rotating running indicator at the base of the hand continuously confirms the watch is functioning correctly.
Diameter and materials
The satin-brushed 316L stainless steel case measures 45 mm in diameter for 14.9 mm in thickness, a size that asserts the piece's instrument vocation. The unidirectional ceramic rotating bezel carries a double scale allowing dive time to be tracked both before and after the retrograde hand returns. The black dial hosts white Super-LumiNova hour markers and a magnifying lens set over the jumping hour window, the whole protected by an anti-reflective sapphire crystal. The screwed steel caseback closes off this construction built for water.
Water resistance
With 250 m / 25 bar water resistance, the Hydrosphere Blackfin belongs to the category of dive watches genuinely usable underwater. The screw-down crown and screwed steel caseback lock down the case, while a helium escape valve lets accumulated gas escape during saturation diving ascents. The unidirectional ceramic bezel completes this safety setup by preventing any accidental extension of the displayed dive time. The white luminescent hour markers guarantee legibility in the darkest waters.
Accessories
The watch ships on a brushed 316L steel bracelet screwed to the case, fastened by a folded-blade deployant clasp fitted with an extension system that allows it to be worn over a wetsuit. RESERVOIR includes an additional black rubber strap, lighter and better suited to sessions at sea, making it easy to change up the piece's look. The set arrives in a waterproof container box, consistent with the model's marine world and useful for transporting the watch while travelling or on a boat.
Warranty
RESERVOIR covers the Hydrosphere Blackfin with a 2-year warranty, extended to 3 years after online registration of the watch on the brand's website. This free extension simply requires declaring the piece and its reference number after purchase. International coverage makes it easier to get servicing for a Swiss Made model distributed in several countries. For a dive watch with a proprietary module, it remains advisable to have the water resistance periodically checked before any intensive underwater use.
RESERVOIR Hydrosphere Blackfin The pros
and cons
- Unidirectional ceramic bezel, double scale
- Integrated helium escape valve
- Patented 124-part module
- Waterproof container box included
- Warranty extended to three years
- Power reserve limited to 37 hours
- Unusual reading requires adaptation
- Delivery available in France only
- Not ideal for small wrists
Discover all the brand's models!
Prices and technical specifications are subject to change. Content and photos are not contractual.
