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Longines HydroConquest 41mm Mens Watch Blue Stainless Steel
Ref. L37904966
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Stepping up in the same colour and case shape
The HydroConquest has always occupied the pragmatic end of Longines' catalogue — a proper diver built to work rather than to pose — and this iteration marks a genuine step forward for the line. The ceramic bezel insert coordinates with the sunray blue dial, and the move away from oversized Arabic numerals toward applied geometric indexes gives the whole face a cleaner, more considered character. The movement underneath is the more significant change: the L844.5 is a true flyer GMT, meaning the local hour hand adjusts independently in one-hour steps without touching the running seconds — a distinction that separates it from the cheaper approach of stopping the movement to reset. At 12.9mm thick for a watch rated to 300m, it wears closer to the wrist than most divers at this depth rating, and the 48mm lug-to-lug span keeps it proportional on a range of wrists despite the 41mm width. The silicon balance spring takes it well beyond standard anti-magnetic ratings, which matters more for a GMT traveller passing through airport security than it does underwater. The bracelet's micro-adjustment clasp requires no tools — useful at altitude when a wrist swells, or simply across the seasons.
- Reference
- L37904966
- Brand
- Longines
- Collection
- HydroConquest
- Case size
- 41mm
- Case thickness
- 12.9mm
- Lug width
- 21mm
- Case material
- Stainless steel
- Case shape
- Round
- Dial
- Blue
- Crystal
- Sapphire
- Bezel
- Rotating
- Movement
- Automatic
- Calibre
- L844
- Functions
- GMT, Date
- Water resistance
- 300m
- Bracelet / strap
- Stainless steel bracelet
- Strap colour
- Silver
- Clasp
- Folding clasp
- Lume
- Luminous
- Retailer
- Mappin & Webb
Additional specifications
- Lug-to-lug
- 48mm
- Power reserve
- 72 hours
Learn more about Longines
Auguste Agassiz began trading watches in Saint-Imier in 1832, but the modern company dates from 1860, when his nephew Ernest Francillon built a factory in the meadows beside the Suze — the longines of the local dialect — and consolidated the scattered outworkers of the region under one roof.
Longines registered its winged hourglass in 1889. It is the oldest watch trademark still in continuous use.
The company's identity was built on precision and on timing things in public. It supplied chronographs for the first modern Olympic events it timed in 1896, timed the 1912 Federal Gymnastics Festival with a broken-wire mechanism accurate to a hundredth of a second, and developed the photo-finish camera and the quartz timing devices used across twentieth-century athletics.
Its aviation associations are equally deep. Longines instruments were carried by Charles Lindbergh across the Atlantic in 1927, and the Hour Angle watch, designed to Lindbergh's own specification to simplify longitude calculation, remains in the catalogue. Amelia Earhart and Howard Hughes both navigated by Longines.
The house was among the most decorated at nineteenth-century observatory trials, holding numerous precision records. Since joining the Swatch Group in 1983 it has occupied the accessible-heritage position: exclusive ETA-based movements, archive-driven designs through the Heritage line, and volume that makes it one of the group's most important brands.
- 1860
- Ernest Francillon builds the factory at Les Longines.
- 1889
- The winged hourglass is registered — the oldest watch trademark in use.
- 1912
- Broken-wire timing achieves hundredth-second accuracy.
- 1927
- Lindbergh crosses the Atlantic with Longines instruments.
- 1983
- Becomes part of the Swatch Group.
Also in 7 collections
This watch appears in the Longines HydroConquest range (42), Back in Stock (3,734), Stainless Steel Watches (2,581), Automatic Watches (1,570), Blue Dial Watches (714), Sports Watches (707) and Dive Watches (505).
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What the specifications mean
A mechanical watch built to be worn hard and got wet.
Strengths
- 300m water resistance, rated for actual diving
- 48mm lug-to-lug keeps the 41mm case wearable
- Sapphire crystal, which resists scratching
- 72-hour reserve survives a weekend off the wrist
- Luminous hands and markers for low light
Longines HydroConquest alternatives
Watches from other brands at a similar price, style and size, so you can see what else your budget can buy.
| Specification | L37904966 | 129369 | R32154208 |
|---|---|---|---|
| Price | £2,650 | £3,000 | £2,500 |
| Case size | 41mm | 41mm | 42mm |
| Water resistance | 300m | 300m | 300m |
| Movement | Automatic | Automatic | Automatic |
| Strap | Stainless steel bracelet | Stainless steel bracelet | Titanium bracelet |
| Power reserve | 72 hours | — | 80 hours |
| This watch |
| Closely matched |
Your new watch
Frequently asked questions, and things you should know about this watch
Can I swim with it?
Yes. At 300m it is rated for swimming, snorkelling and recreational diving.
Water resistance explainedWill the glass scratch?
Unlikely. Sapphire is second only to diamond in hardness and shrugs off everyday marking.
Sapphire, mineral and acrylic comparedDoes it need a battery?
No. It is automatic — the motion of your wrist winds it, and there is no cell to replace.
Quartz, automatic and solar comparedHow long does it run for when it's not worn?
About 72 hours fully wound — enough to sit off the wrist over a weekend and still be running.
What size strap does it take?
21mm. Any strap of that width will fit, and on most modern watches quick-release bars make the swap a two-minute job with no tools.
Will it fit my wrist?
Lug-to-lug is 48mm, which suits wrists from roughly 16.5cm (6½ inches) upward.
Lug-to-lug decides fit more than case diameter does.
How to size a watch to your wristIs it a men's or women's watch?
Listed as men's.
Cheapest place to buy
Both Mappin & Webb and Goldsmiths list it at £2,650, so choose on delivery and warranty rather than price.
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