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Louis Erard Le Régulateur x Massena Lab Limited Edition 42mm Unisex Watch Gold
Ref. 85237AA75.BVA103
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The Régulateur has been part of Louis Erard's catalogue since 2011, but this 2022 collaboration with William Massena gave it a specific ancestry to answer to. The dial draws directly from the marine chronometers of Ferdinand Berthoud — those instruments of the late eighteenth and early nineteenth centuries that managed to be both beautiful and exactly right — with Antide Janvier's classicism cited as a further reference point. Only 178 pieces were made, a number chosen deliberately: the edition size is itself a statement of intent about the partnership. The Gold variant is distinguished from its rhodium-dialled sibling solely by that dial treatment; everything else is shared. The regulator layout separates what most dials conflate — hours run in a sub-register at twelve, the central hand sweeps minutes alone, small seconds sit at six — and on a gold-plated grained dial with blued steel hands, the result reads with the unhurried clarity of an instrument dial rather than a decorative one. The rhodium-plated flanges and counters with their diamond-cut corners introduce just enough contrast to keep the surface from flattening, and the domed sapphire above it adds a further layer of depth. At 49.6mm lug-to-lug the proportions are substantial, but the curved lugs pull the case closer to the wrist than that figure implies. Through the sapphire caseback, the SW266-1 carries a custom openworked rotor with a black lacquered Louis Erard symbol — the most visible evidence of the finishing work done to what is otherwise a capable but unremarkable base movement. The caseback is engraved individually, and the quick-release bars on the black calf leather strap make changing it straightforward for a watch that will suit more than one context.
- Reference
- 85237AA75.BVA103
- Brand
- Louis Erard
- Case size
- 42mm
- Case thickness
- 5.60mm
- Lug width
- 22mm
- Case material
- Stainless steel
- Case shape
- Round
- Dial
- Gold
- Crystal
- Sapphire
- Movement
- Automatic
- Calibre
- SW266-1
- Functions
- Small seconds, Skeleton dial
- Water resistance
- 50m
- Bracelet / strap
- Leather strap
- Strap colour
- Black
- Clasp
- Deployant clasp
- Lume
- Luminous
- Retailer
- Goldsmiths
Additional specifications
- Lug-to-lug
- 49.60mm
- Power reserve
- 38 hours
- Warranty
- 3 years
- Strap
- Interchangeable
Manufacturer’s guarantee
Your new watch
Frequently asked questions, and things you should know about this watch
Can I swim with it?
Showering yes, swimming no. 50m covers splashes and brief immersion, but a swimming stroke generates well above the pressure that figure describes.
Will the glass scratch?
Unlikely. Sapphire is second only to diamond in hardness and shrugs off everyday marking.
Does it need a battery?
No. It is automatic — the motion of your wrist winds it, and there is no cell to replace.
How long does it run for when it's not worn?
About 38 hours fully wound — so it will usually stop if you leave it off overnight.
What size strap does it take?
22mm. 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 49.60mm, which suits wrists from roughly 16.5cm (6½ inches) upward.
Lug-to-lug decides fit more than case diameter does.
Is it a men's or women's watch?
Listed as unisex, and at this size it suits any wrist that takes the dimensions.
Cheapest place to buy
Goldsmiths is the only UK retailer we track stocking this reference, so there is nothing to compare it against today.
Who are Goldsmiths?
Goldsmiths has been selling watches in Britain since 1778 and is part of the Watches of Switzerland Group, which is listed on the London Stock Exchange. They are an authorised dealer, so a watch comes with the manufacturer’s own warranty.
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