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Louis Erard 2340 Slate 40mm Mens Watch
Ref. 35123TA02.BMT12
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A tonneau-shaped sports watch in titanium and stainless steel, measuring 40mm across and just 8.95mm thick. The satin-finished titanium case middle sits alongside a polished stainless steel bezel, lugs, and crown, while the screw-down caseback keeps the profile clean. At 92 grams, it wears lightly on the wrist. The slate blue dial carries a lacquered horizontal wave pattern, with rhodium-plated diamond-cut indices and a white railway track chapter ring. A small satin plate engraved with the "LE" logo sits at three o'clock. Hands and markers are treated with Super-LumiNova in blue emission. The domed sapphire crystal has anti-reflective coating on both sides. The fully integrated multi-link bracelet pairs satin titanium outer links with polished steel centres, closing with a concealed butterfly clasp. Power comes from a Sellita SW300-1 automatic with a 56-hour reserve.
- Reference
- 35123TA02.BMT12
- Brand
- Louis Erard
- Case size
- 40mm
- Case thickness
- 8.95mm
- Case material
- Stainless steel
- Dial
- Blue
- Crystal
- Sapphire
- Movement
- Automatic
- Calibre
- SW300-1
- Water resistance
- 50m
- Bracelet / strap
- Stainless steel bracelet
- Strap colour
- Silver
- Clasp
- Folding clasp
- Lume
- Super-LumiNova
- Retailer
- Goldsmiths
Additional specifications
- Lug-to-lug
- 41.50mm
- Power reserve
- 56 hours
- Weight
- 92g
- Origin
- Swiss made
Learn more about Louis Erard
Louis Erard was born in La Chaux-de-Fonds in 1893, into a town then producing a large share of the world's watches. He worked in its workshops, founded a watchmaking school in 1929, and set up a casing and assembly business with André Perret the same year. The first watches under his own name followed in 1931.
Assembly was the trade at the time: components came from independent artisans and the assembler built, adjusted and finished the watch. By 1937 Erard employed more than sixty people and was selling internationally.
The quartz crisis did its usual damage. The company was sold in 1991 and production moved to Le Noirmont in the Jura, then sold again in 2003 to a group led by Alain Spinedi, who refocused it on mechanical watches at prices that undercut everyone doing similar work.
The regulator became the signature — the dial layout that separates hours, minutes and seconds onto their own axes, borrowed from precision reference clocks, and rarely seen at this price.
What has made the brand's recent reputation is collaboration: limited editions with independent watchmakers whose own work is unobtainable, among them Vianney Halter, Konstantin Chaykin and Alain Silberstein, on Sellita and Valjoux movements.
- 1929
- Founds a watchmaking school and a casing business with André Perret.
- 1931
- The first watches carry the Louis Erard name.
- 1991
- Sold, with production moving to Le Noirmont.
- 2003
- Relaunched under Alain Spinedi around mechanical watches.
- 2020
- Collaborations with independent watchmakers define the brand.
Also in 4 collections
This watch appears in Stainless Steel Watches (2,782), Automatic Watches (1,540), Blue Dial Watches (758) and Limited Edition Watches (187).
Manufacturer’s guarantee
What the specifications mean
A mechanical watch for everyday wear.
Strengths
- 40mm suits most wrists
- 8.95mm is unusually slim for a 40mm case
- 41.5mm lug-to-lug keeps the 40mm case wearable
- Sapphire crystal, which resists scratching
- Luminous hands and markers for low light
Worth knowing
- 50m suits rain and handwashing, not swimming
Louis Erard 2340 Slate alternatives
Watches from other brands at a similar price, style and size, so you can see what else your budget can buy.
| Specification | 35123TA02.BMT12 | L29374726 | BM0A10518 |
|---|---|---|---|
| Price | £3,290 | £3,250 | £3,200 |
| Case size | 40mm | 40mm | 40mm |
| Water resistance | 50m | 50m | 50m |
| Movement | Automatic | Automatic | Automatic |
| Strap | Stainless steel bracelet | Stainless steel bracelet | Leather strap |
| Power reserve | 56 hours | 52 hours | 120 hours |
| This watch | Closely matched | Closely matched |
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.
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 56 hours fully wound — enough to survive a night off the wrist, but not a full weekend.
Will it fit my wrist?
Lug-to-lug is 41.50mm, which suits wrists from roughly 15cm (6 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, though at 40mm it sits in the range that suits anyone.
Cheapest place to buy
Goldsmiths is the only UK retailer we track stocking this reference, so there is nothing to compare it against today.
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