One of the crucial pieces of information that many people look for when considering a watch is the width/diameter of the case, a number usually expressed in millimeters. This is a measurement that is important to many watch buyers, who in evaluating the suitability of one for purchase, has to get a sense of whether it is too big or too small, a concern especially significant for those who’s wrist size resides at the upper or lower limit of possibility.

With the wide range of offerings in case widths as well, one also establishes, by way of experience, a range within which a probable acceptable fit might occur. The importance of this is obvious; too small, and the watch has barely any presence, too big, and one runs the risk of looking like one is wearing a clock on the wrist.

Not helping the situation as well is the trend over the past decade or so of case sizes going up, often testing the limits of sanity at each new mark. Years ago, before the trend of large watches took hold, 36mm, the typical size of a men’s Rolex for decades, was considered large.

Nowadays, 36mm is considered small for men, and many women actually take it as the minimum size to wear. Men, of course, have moved on to larger sizes. Typically resting at the 40-42mm range, or sometimes at 44mm with most Panerai, and onwards to 46mm or more for watches such as the IWC Big Pilot, or some of the 48mm Breitling watches.

The choice of the diameter of a watch is a very personal thing. Most people come to a rough idea of the range of widths that they are comfortable with, tending to limit their choice of watches to these numbers that they already know.

Yet as most experienced watch collectors discover over time, the apparently self-evident truth of a number does not correlate to the actual experience of wearing the watch. Indeed, as some come to discover, the stated width of a watch case can in fact feel very different compared to other watch cases of the same width on the wrist.

Case in point, the new HYT H-Zero that startled the world this Baselworld with its minimalist design, which deviates markedly from the aesthetic language that has already been established with all preceding HYT watches. That aside, the one comment that would come up time and time again in the many Instagram posts and articles about the watch, is of its immense wearability. And this despite its stated case diameter of 48.8mm. How can this be?

The answer as I shall explain, lies in the flawed measurement that the watch industry in general has been using for a long time. A measurement that takes into account only one element of the total picture. It might actually, in fact, be important only to the extent of figuring out how big the dial might appear, seen within the confines of the case, but do nothing for predicting wearability.

The true measurement then to keep in mind, that far surpasses the traditional case width measurement we all know in usefulness, is a watch’s lug-to-lug distance.

Now this is not a new idea, and in fact one hears it mentioned every now and then, with Tim Mosso in his “Talking Hands” videos on the “watchuwantinc” Youtube channel as a particularly avid exponent of its use. It is essentially the vertical distance between the lugs, or more specifically, the distance between the points in the strap or bracelet that attaches to the lugs.

The basic idea is this: A watch is typically flat on its underside, and the points with which the bracelet or strap curves down, marks the limit of the distance that a wrist can take in wearing a watch. It’s easy to imagine this as long as the one rule we stick to is that the lugs should not overhang above and below the diameter of the wrist. With this rule respected, all one really needs to know then is one’s personal lug-to-lug distance, and keep to that when choosing a watch. Of course, it helps if there is a kind of industry wide consensus on implementing this measurement in watch specifications, and hopefully this article will make it evident of how useful it can be.

What is clear from this point is that it’s not just the round of the case that matters but also how long the lugs are. On some watches, they can be very long, indeed, throwing off the one’s sense of its wearability when it finally comes onto the wrist. On some, like the HYT H-Zero, they are essentially nonexistent. In either case, if one were to rely on a case width as the only criteria to determine if a watch is suitable to wear, then potentially, it will limit the number of watches one can consider if one does not have a chance to try them on in person.

Let’s look at some examples now to illustrate these points.

First we start with the HYT H-Zero, the brand’s most recent release shown here on a lady’s wrist (image 1). Now she tells me that she typically does not go over 40mm for her 15cm circumference wrist, when she chooses a watch, but this watch looks great here. Why?

We find here that due to the essentially lug-less design of the HYT H-Zero the watch measures 48.8mm (image 2), or the stated case diameter.

In image 3, we have the HYT H1 above and the HYT H-Zero below, showing just how much further apart the lug-to-lug distance is on the H1.

HYT H-Zero
The HYT H-Zero the watch measures 48.8mm
HYT H1 above and the HYT H-Zero below, showing just how much further apart the lug-to-lug distance is on the H1.

The HYT H1 is 53mm, lug to lug, despite the stated case width of 48.8mm, the same as the HYT H-Zero (image 4).

Here we see the difference in wearability on my wrist with the HYT H1 on left versus the HYT H-Zero (image 5), with the H1 having a visibly larger stance due to its lugs. Essentially, due to the unique lug-less design of the H-Zero, the rubber strap is attached directly to the round of the case making it wear much smaller than the H1. When you make a comparison of my wrist with the H-Zero, you’ll find that the strap actually turns down much quicker, and therefore, suits someone with a smaller wrist.

The HYT H1 is 53mm, lug to lug, despite the stated case width of 48.8mm, the same as the HYT H-Zero.
HYT H1 on left versus the HYT H-Zero

Now this whole story gets even weirder, and for this I have the following watches for comparison, with their stated case widths in brackets: The IWC Pilot Chronograph ref. 3717 (42mm), the Maurice Lacroix Flyback Chronograph Annuaire (42mm) and the Lange 1 (38.5mm).

Here we find that despite the IWC and the Maurice Lacroix having the same stated case width of 42mm, you can see that the different lug lengths will cause the watches to wear very differently despite the same stated measurement (image 6).

It’s even more amazing here, where we find that despite the Lange 1 being 38.5mm in case width, it wears comparably with the Maurice Lacroix at 42mm, due to the lugs of the Lange 1 extending to almost the same measurement (image 7).

IWC and the Maurice Lacroix having the same stated case width of 42mm.
Lange 1 being 38.5mm in case width, it wears comparably with the Maurice Lacroix at 42mm, due to the lugs of the Lange 1 extending to almost the same measurement.

And here’s a picture of the IWC with the HYT H-Zero (image 8 & 9). At 42mm versus 48.8mm in the specifications, it is clear that the numbers don’t tell the full story. Not sure if you can wear a 48.8mm H-Zero? If you are comfortable with the 42mm IWC, then you shouldn’t have any problem.

And how about this for a kicker? Here we have the HYT H-Zero versus the Lange 1, where we find the lug-to-lug distance being essentially the same (image 10). Therein lies the surprise. It basically means that if you are in the market for a HYT and you found the sizes of the previous collections to be too large, you can now be assured that so long as you can wear a Lange 1, you can wear an HYT H-Zero, which essentially means everyone can wear one since the Lange 1 can be often spotted on both men and women.

IWC with the HYT H-Zero, 42mm versus 48.8mm
IWC with the HYT H-Zero, 42mm versus 48.8mm
HYT H-Zero versus the Lange 1

The process of deciding whether to buy a watch is something that should always be made easier. Especially in our current Internet dominated world, where one can find out about watches that might not be available to see in person. For all this ability to search out the rare and unique, most buyers still have to contend with the barrier of whether the size of a watch is suitable. While the current usage of case width measurement is useful, it is not the complete picture, and might lead one to not consider a watch that might fit well or to buy one that does not fit well at all. What needs to change in this instance is an industry wide standard that adds lug-to-lug measurements to the picture, and a clear understanding of how the number can be interpreted.

In that case, it gives potential buyers, who do not have the ability to see the watch in person a better judgment before committing, and it avoids situations where watches like the HYT H-Zero, the Corum Bubble (with the 52mm version being the best size for most men) or even the Jaeger-LeCoultre Reverso (with its rectangular shape offering a slightly different challenge) are struck off a consideration list.

Consider this then as my modest proposal for us all to adopt this as an industry standard.