Watch case diameter is an important consideration when purchasing a new timepiece. When you purchase a watch, you need to know how to select one that’s right for your wrist, as a single size won’t be right for everyone. 

For men’s watches, diameters range from 35mm to 46mm, and some are even larger. If your wrist is between 14cm – 18cm, a small or medium watch with a diameter of 38mm, 40mm, or 42mm will look good for you. 

If your wrist is 18cm and above, choose a larger case, such as 44-46mm in diameter.



Although some people are attracted to watches with bold designs, big dials and large cases could appear unflattering if you have a small wrist. 

On other hand, even people with bigger wrists also prefer to wear slim watches because they are more elegant, classy, and never out of style.

Whether you are into a sporty, classic dress, or robust timepieces, we made a list of the four best 38mm watches that you can wear on either a formal or casual occasion.

Let’s jump right in! 


Omega Seamaster Aqua Terra

The Omega Seamaster Aqua Terra 38mm is a distinctive, sporty watch that packs the in-house caliber Omega 8800 movement. It feels extremely capable on the wrist, and could be used in any situation.

There isn’t a part of the timepiece's design that feels overly traditional, but it draws on decades of Omega’s design ideals. 


Source: Monochrome Watches


Its dial design replicates the deck pattern on luxury yachts, while its hour and minute hands draw you right in. The minute hand sports an arrow tip, which is a clear nod to the broad arrow design. 

Omega offers the Aqua Terra on three different straps and bracelets for you to choose from, including a three-link oyster style, alligator leather, and a rubber strap. 

If you’re looking for a versatile everyday watch that is both conceptually and visually balanced, the Omega Seamaster Aqua Terra 38mm is the way to go! 


Blancpain Fifty Fathoms Bathyscape

Blancpain released the new 38mm version of the Fifty Fathoms Bathyscaphe in black or blue, which feels a lot more vintage than the previous 43mm of the Bathyscaphe.


Source: A Blog to Watch


The watch comes in two versions: a black-ish dial and bezel, and a limited edition with an "Abyss Blue" dial and bezel. Of course, this watch looks amazing, and uses some of the best components in the world of watchmaking. 

The stainless steel case is brushed throughout which makes the watch look a bit more substantial than if it were polished, which is a robust feature.

The case measures 38mm and it is a great size for classic watch fans and it can be worn by almost anyone. A lot of people including men and women wanted a 38mm Fifty Fathoms Bathyscaphe as this watch easily works in both casual and formal settings. 

One small thing is the price, as it retails for more than a Rolex Submariner. If you like the looks of this watch, you may find that Seiko Mod Watches like a 62MAS style watch are a little more affordable. 


Hamilton Khaki Field Mechanical

To many, the Khaki Field Mechanical is the quintessential modern evolution of a classic field watch. The Khaki Field line works with a smart casual outfit, or in a flannel shirt in the woods. 


Source: Wrist Watch Review


The Khaki Field Mechanical 38mm is a watch for traditionalists and military nerds out there who want a taste of the old world without buying a vintage watch. 

Hamilton updated the movement in 2019 to its own H-50, which is a handwinding Swiss movement that packs an 80 hour power reserve. 

It is available on different NATO straps, varying between nylon and leather and with numerous color choices. One more great thing about the Khaki Field Mechanical is the price point, as these can be found new for less than $450.  


Rado HyperChrome Captain Cook

Coming in at 37.3 millimeters in diameter and with an unlumed bezel, the Rado HyperChrome Captain Cook is a pure vintage sports watch you can buy today. 


Source: Ingenio Virtual


This watch is based on a piece made by Rado back in 1962, also known as the Captain Cook. The size is charming and really feels like a totally vintage piece, especially with the curved dial.

In addition to the use of ceramic and sapphire, the impressive movement, called the calibre C07.611, is a big upgrade to the modern version. The curved, sunburst gray dial has hues of brown which just adds to the classic appeal. 

It feels like a vintage watch from the 1960s, with all the gloss of a modern piece. 


Modding Your Own 38mm Watch

Even with all these amazing options available, you may still prefer a 38mm watch that you modded yourself. You can build it to your exact specifications and make it as flashy, or as functional as possible. Here are some of our 38mm cases that you would want to check out:


If you find the OEM SKX013 case a tad too small with its 37mm diameter, you can opt for our NMK925 case that is exactly 38mm with no crown guards for a slimmer profile. It has the same 200m water resistance that the original boasts of and is compatible with OEM and our aftermarket parts.



If you’re looking for something a bit more newbie-friendly, our best-selling case is our NMK912 bundle which already includes a crystal, crown and caseback, requiring only minimal assembly once you receive it. It is the perfect case as a field watch, and you can also dress it up for a more formal look.


Source: @wat_gear on IG

And for military fans, be sure to check out the NMK931 field case which was inspired by the Serica 4512, which was in turn inspired by one of the watches from the Dirty Dozen; a collection of 12 watches from WWII. The crystal is already pre-installed for you, eliminating one of the hardest parts of modding a watch.

Mid Sized Watches Rock 

Finding the right watch for your wrist will help you enjoy watches even more, and if you want to get into midsize watches, you aren’t alone. 

In addition to the four watches mentioned above, Seiko also has a wide collection of midsize timepieces, including the ones around 38mm. A Seiko like the SKX013, could be the perfect fit for you. 

We offer loads of watch mod parts for Seiko mods, so if you want to make your own midsize diver, or field watch, we can help. 

At namokiMODS we have loads of aftermarket SKX007 parts. Check out our extensive online catalog for more about all the watch spare parts we offer, and buy from the best - namokiMODS! 

August 10, 2022 — Jeremiah A

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