Mondaine Ultra Thin Swiss Railways Watch Review


Mondaine Utra Thin face

The Swiss Railways Watch – based on the immortal Swiss railway clock – is the world’s most legible timepiece. The question facing Mondaine: how do you improve on perfection? The watchmaker has introduced numerous variations, including reversing the dial colors (white hands on a black dial) and adding complications (e.g., the Sports Day Date  and Stop-2-Go).  But it’s the Mondaine Ultra Thin that cracks the nut . . .

Mondaine Ultra Thin being thin

The obvious improvement over the 36mm Swiss Railways Classic Pure and its horological cousins: the Ultra thin is thin. 6.2mm, to be exact.

For comparison purposes, the Bulgari Octo Finissimo Automatic is 2.23mm from top-to-bottom. The quartz-powered Citizen Eco-Drive One is 2.98mm thick.  More realistically, the Ultra Thin competes against your standard-issue daily wear timepieces.

Mondaine Ultra Thin in the garden

At the top end, the Rolex Oyster Perpetual 39 is 11mm thick. At the bottom., the SWATCH Big Bold Jellyfish is 11.75mm thick. Somewhere in between, the Longines Conquest V.H.P. is 12.9mm thick. And just for fun, the Rolex Submariner is 13mm thick.

Mondaine vs. Mondaine

So the Mondaine Ultra Thin is thinner than the average watch, but not super mega ultra thin. Here’s money shot: the Swiss Railways Ultra Thin (left) vs. the Sports Day Date. It’s 6.2mm vs. 10mm. What a difference 3.8mm makes!

Like all thin watches, the Ultra Thin has a totally different look and feel than the portlier timepiece. It’s far more elegant and significantly lighter on the wrist (1.7 ozs. vs. 2.1 ozs.). Apologies to body positive people, but when it comes to watches, thin is in (e.g., Grand Seiko’s new Hi-Beat movement).

Mondaine Ultra Thin sitting up

On the downside, the Mondaine Ultra Thin’s underside is convex and the lugs are dead straight. If you like to wear your watch loose, the Ultra Thin will cha cha slide to the side. The only way to keep the watch centered: lash it down with the plasticky leather strap. The Texas summer heat says that’s a bug, not a feature.

When it comes to the Ultra Thin’s case diameter, flip the script.

For most purposes, 39mm is the Goldilocks size for a watch. Any watch. Any wrist. (The Paneristi may disagree, but they’re different from you and me.) I don’t care what position you played on your high school football team, a 41mm watch is BIG. Thanks to its barely-there steel bezel and minimalist face, the 41mm Mondaine Ultra Thin looks WAY BIGGER.

Railways watch wears you

This is not a watch for the horologically shy and retiring. As our Russian readers might say, in Mondaine, watch wears you. Sure, the XXL Railways Watch slips under a shirt cuff more easily than a stealth bomber evading enemy radar. But if you’re exercising your right to bare arms, the Ultra Thin is Ultra Obvious.

Not that there’s anything wrong with that-especially if you’re sight impaired (i.e., old). This is the world’s most legible watch. Where the standard Swiss Railways watch features at-a-glance readability, the Mondaine Ultra Thin 41 delivers at-a-glance unavoidability.

RONDA 783 HH2 movement

Is it me, or does the Ultra Thin’s red second hand – modeled after the Swiss railways conductor’s baton – seem to take forever to circumnavigate the dial? Not to belabor the point (much), if you can’t tell the time with the Ultra Thin, you can’t tell the time. Even the 44mm Torgeon Turnstone is jealous.

RONDA 783 HH2 movement

A quartz RONDA 783 HH2 movement powers those blocky, Minecraft-style hands. RONDA’s 2.5mm thick temporal engine will keep on keeping on for 42 months – or longer if you pull out the stem (reduces power consumption by 70 percent). Resistant to shocks, extreme temperatures and magnetic fields, the Swiss engine’s a miracle of modern micro-technology.

But nothing compared to even the most kludgy smartwatch. Which is fine. If ever there was a mission-focused watch, the Mondaine Ultra Thin is it. From the product description at (no commission paid): “Function: Time.” And there you have it.

Mondaine Ultra Slim caseback

Or will if you surrender $340. The money buys you the Jumbotron version of a classic design, a watch that takes zero effort to operate, read, wear or own. The only significant omission: luminescence. There isn’t any. (Paging Indiglo.) But if you believe that less is more, the Ultra Thin is more watch than you’ll ever need.

Model: Mondaine Ultra Thin Simply Elegant White
Price: $340 from (no commission on link)


Movement: quartz RONDA 783 HH2
Case size/diameter: 41mm
Case material: Stainless Steel Polished
Caseback: Stainless steel caseback closed with Screws
Crown: Regular Gasket
Crystal/Glass material: Sapphire
Water resistance: 30m/ 100ft.
Strap/Bracelet: Genuine Leather
Width at lug: 22mm
Function: Time

RATINGS (out of five stars):

Design * * * * *
Minimalist masterpiece based on the legendary Swiss Railways clock.

Legibility * * * *
The world’s most legible watch writ large. Star deducted for zero luminescence.

Comfort * * *
Thin is light, light is comfortable. BUT the Ultra Thin’s convex caseback and straight lugs mandate lashing the strap to your wrist to keep it centered.

Overall * * * *
A watch for the ages: zero effort to operate, read, wear or own. Final star deducted due to nighttime and comfort considerations.


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