Most watch enthusiasts have certainly heard of the Blancpain Fifty Fathoms. It is the first modern diver’s watch and an exemplar in watchmaking history.

Given the stature and price of the Fifty Fathoms, it’s not surprising why there have been endeavors by watch aficionados to recreate the Fifty Fathoms in the Seiko mod community.


Source: @dixanwatches on IG


The goal of creating a Blancpain Fifty Fathoms Seiko homage – AKA the Fifty-Five Fathoms – has been a success and  the watch modding community has also made different and unique designs that look great. 

Best of all, you can mod a Seiko for a fraction of the price!


What is a Fifty-Five Fathoms?

Dive watches are extremely popular for their rugged build quality, versatile good looks, and timeless style. However, as mentioned, dive watches as we know them today wouldn’t exist without the Blancpain Fifty Fathoms. 

First released in 1953, the original Blancpain Fifty Fathoms, with a unidirectional rotating timing bezel, a patented O-ring seal and double-sealed crown system, and a hefty dose of water resistance, has created a genre that would soon become standard in the watchmaking industry.


Source: Hairspring


The timepiece was designed mainly for military use. It was also commissioned by Captain Robert Maloubier and Lieutenant Claude Riffaud, commanders of the French Combat Diving School, for use in underwater missions. 

Elite divers depended on the Fifty Fathoms for coordination and ensuring personal safety during difficult missions before dive computers came into widespread use.


Source: Mariners Point Pro


The watch gets its name from the US customary systems unit of length called the “fathom,” which is equal to six feet. As the name implies, the Fifty Fathoms was rated for diving up to 91m or 300ft, which was as deep as a diver could go without a compressed oxygen tank.

Since its first use, the timepiece has gone through multiple design iterations in terms of aesthetics and innovation. Blancpain is still making the Fifty Fathoms and it’s gone quite a bit upmarket with the brand’s current status as a seller of haute timepieces.

Whether you’re a newbie to watch modding or a seasoned veteran, if you’re looking for how to recreate the original Fifty Fathoms diver’s watch or even incorporate designs of your own, we're here to show you how to do it. 

Keep reading!


Suggested Base Watch: Seiko SNZH55

Most modification projects begin with a base watch that you can customize, so you will need a base that looks similar to the Fifty Fathoms. In addition to the most popular Seiko modding selection, the SKX007, its successors such as the Seiko 5 Sports SNZH55 are a good place to get started.


Source: on IG


While the SNZH55 carries a 7s36 movement, which does not hack or handwind, you can start fresh with a 4r series movement, and use a dial that you like. 

The Seiko SNZH series is already based on the Blancpain Fifty Fathoms and it could be called an homage in itself. Therefore, the most defining features of the “FF” are its bezel, hands, and dial. So, if you had a working watch that you could use as a base, your job would be easier.


Build Your Own Seiko Fifty-Five Fathoms Homage

Modding a watch is one of the best ways to bring your imagination to reality, so only your creativity will limit your results.

Depending on your level of commitment, there are a few modifications possible such as its dial, hands, sapphire crystal, bezel, bezel insert, chapter ring, and strap. Among these, swapping the dial to get the correct indices as well as the "Fifty-Five Fathoms" script are the most common ones.


Source: @gonciuu on IG


Not only that but many dials are very similar to the Fifty Fathoms, such as the Seiko CT825 with the Black and Gold watch dial. Some manufacturers sell their own take on the Blancpain Fifty Fathoms as well. 

A dial is one of the most visually important parts of the watch because it carries heavily the look and feel of a timepiece. So, the face of the watch would be the most crucial part of your watch mod.



On the other hand, there are also many hand designs in the aftermarket space. If you’re looking to use Seiko-compatible mod parts, there’s a set of Fifty Fathoms polished finish hands for you.

Furthermore, bezels for the SNZH55 model are hard to find – but here at NamokiMODS, we have glass bakelite bezel inserts inspired by the Fifty Fathoms style, which make any Seiko mod amazing to see. 


A Fifty-Five Fathoms Done Right

You can create an amazing Fifty-Five Fathoms with SKX007 Parts, but we have loads of other Seiko spare parts if you want to try something different. Using the best Watch spare parts makes any mod idea better, so work with namokiMODS, and make the best mods out there!

Happy modding!

February 25, 2023 — Jeremiah A


Allan said:

Thanks for Your Sharing Great Work on this Fanthom iam a Big Blancpain Fan and A Bigger new in modding can you help me set up a List to buy and order for at watch i can mod with all the Blancpain mod parts 🙏 i pay offcus in front best regards Allan from Denmark

Michael Risen said:

This is my second time writing you without a response.

I am interested in purchasing a custom built 55 Fathom Watch

. Can you take on this Project?

Please respond.

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