What is the EPSA Super Compressor Diver's Watch Case?

If you are familiar with EPSA cases, you are probably a vintage watch enthusiast.

The design and functionality that come from its distinctive case will always have a timeless coolness, no matter how much time passes.

In today's article, we will explain about this super compressor.

The table of contents looks like this.

1. What is the EPSA Super Compressor?

2. How do you identify a super compressor?

3. How many Dual Crown case sizes are there?

4. What is the difference between Compressor, Compressor 2, and Super Compressor?

Finally, here is a summary.

So let's get started right away.

What is EPSA Super Compressor?

EPSA Super Compressor Patent

"Super Compressor" is the trademark name of a diver's watch case manufactured by watch case manufacturer Ervin Piquerez SA (hereinafter referred to as EPSA).

"Contents of the patent"

This is a design that uses the increased water pressure on the case as the depth increases to press the back cover against the O-ring.

As the water depth increases, the water pressure also increases, and the sealing ability also increases.

This mechanism also has the advantage of extending the life of the O-ring (the rubber on the back cover) because the case and back cover are not fully pressurized in places without water pressure.

EPSA made a variety of cases, including single crown, external bezel, and bezel-less models, but we will focus on their signature model, the Double Crown Super Compressor.

EPSA - Various Case Patterns - Single Crown and External Bezel

A feature of the case is that, as the name suggests, the Double (Dual) Crown Super Compressor case typically has two crowns.

The first functions as a normal crown and is located at the 4 o'clock position.

The second is located at the 2 o'clock position and serves to rotate the inner bezel.

Generally, the bezel is located on the surface of the watch, but in the case of diver's watches, some are located on the inside of the crystal, such as those manufactured by EPSA.

This is because there must be no error in measuring a diver's exact dive time.

For example, if the watch were to hit something during a dive and the bezel were to turn, it would change the remaining dive time, which could be life-threatening if the oxygen runs out first.

Therefore, the EPSA Dual Crown Super Compressor has two crowns.

Another feature of the crown is that it is large so that it is easy to operate even while diving.

EPSA's giant crown

EPSA cases are generally designed to withstand depths of up to 666 feet (approximately 200 m).

Benrus Diver's Watch Ultra Deep

Renowned for their extremely high quality and water resistance, EPSA manufactured Super Compressors of various designs from the late 1950s until they went bankrupt and closed down in the mid-1970s.

The fact that items manufactured at that time can still be used today is a testament to their high quality.

Do all Super Compressors have inner bezels?

It is different.

The compressor only refers to the mechanism that seals the case, no other features are relevant.

Generally, they are dual crown, but there are also cases where the Super Compressor is equipped with a single crown.

"Are the larger cases of the dual crown models called 'Super Compressors' and the smaller cases simply called 'Compressors'?" This is also incorrect.

Do all Super Compressors have screw-on backs?

Many of them are true, but some are not.

The Super Compressors manufactured for Enicar are an exception as they do not have a screw-on back.

The one for the Anyca has a bayonet-style back cover, similar to the way a camera lens is attached.

If you don't know much about Enica, please watch this video for a detailed explanation.

How do you identify a super compressor?

The engraving (signature) representing EPSA's Super Compressor

*The mark (signature) representing EPSA's super compressor

EPSA Super Compressor watches can be identified by the diving helmet mark engraved on the case back or sometimes elsewhere.

Most Dual Crown Super Compressor watches (but not all) have a crown with a cross-hatched pattern, also known as a cross-hatched pattern.

Some products also have the manufacturer's signature on top of this mark.

For example, the photo below shows an Enica crown, with the Enica logo painted over the cross-hatched mark.

Crown (mesh pattern) that comes with EPSA case

The image below is of an IWC Aquatimer, but this one does not have a cross-hatched mark and has a fish-like mark.

IWC Aquatimer with EPSA case

Also, if the watch has a screw-on back cover, there should be a spring part inside the edge of the back cover.

The patent numbers for the EPSA Super Compressor are also listed, along with BREVET 317537 and BREVET 337462 for screw-down backs, and CASE 2342 8-65 or BREVET 314962 for bayonet (Enica case) backs.

EPSA Enica case patent number

Are all watches with dual crowns and inner bezels EPSA Super Compressors?


There are many manufacturers producing watches with similar specifications.

There are dual crown and inner bezel watches that are very similar to the cases made by EPSA, but other companies' watches do not use Super Compressor technology on the back cover.

Recently, dual crown replica watches have been seen here and there.

Although these watches feature many of the design features seen on the Super Compressor, such as the dual crown and inner bezel with cross-hatching, they are replicas made by modern emerging manufacturers and are not genuine Super Compressors.

What are the different Dual Crown case sizes?

Differences between the two types of cases from EPSA

Common sizes are 42mm for large dual crown cases and 22mm at the lugs, and 36-37mm for small dual crown cases and 18-19.5mm at the lugs.

When you look at it like this, even the smaller one is still big enough.

Representative models with 42mm cases include the Longines Legend Diver and the Universal Geneve Polerouter Sub.

Models that use 37mm cases include the IWC Aquatimer, Benrus Ultra Deep, and Hamilton Aquadate.

There are also a few Dual Crown Super Compressors available for women, which are 26mm.

Which manufacturers use the Dual Crown Super Compressor?

Droz Super Compressor Dual Crown

The Dual Crown Super Compressor case was extremely popular and was used by a number of watch manufacturers, from well-known names like JLC, Zenith, and Longines to some lesser known names.

Below is a list of companies known to have used Dual Crown Super Compressor cases.



Cupillard Riemme
Girard Perregaux

Le Cheminant

Nivada Grenchen
Universal Geneve
Wittnauer Geneve


What all of these brands have in common is that they all use EPSA cases to make their diver's watches, which makes them very cool.

What is the difference between Compressor, Compressor 2, and Super Compressor?

Compressor Compressor 2 Super Compressor

Both the Compressor and Compressor 2 have snap-on backs.

Compressor 2 is not circular, but has an angular case (e.g. square, cushion-shaped, tonneau).

The Compressor and Compressor 2 are also waterproof, but in a way that is generally found in "fashion" watches and are not designed to be waterproof as diver watches.

The exception is Jaeger-LeCoultre's Polaris, which uses a triple crown compressor case.

Jaeger-LeCoultre Polaris uses EPSA case

In contrast, Super Compressors use a screw-down back, with the exception of Enicar watches, which use a bayonet-type back.

The Super Compressor is available in both single and dual crown configurations.

Where can I get parts for the Dual Crown Super Compressor case?

Many of the key parts exclusive to the Dual Crown Super Compressor are nearly impossible to find.

The crystals vary from case to case, and there are so many different designs available.

The inner bezel is held in place by a crystal and tension ring, which is also a custom made part.

I've heard of cases where it's possible to combine commercially available, versatile crystals, but the results don't seem to be satisfactory.

The star gear that rotates the bezel is not available.

The crown with the cross-hatched lines is also unavailable.

It is possible to use a commercially available crown as a substitute, but watches without genuine crowns will decrease in value.

If you are considering purchasing a Dual Crown Super Compressor, make sure that all the parts are perfectly aligned and working properly.

If you purchase a part that is missing, you may find yourself having to purchase another watch (or multiple watches) with that part in order to get the part you need.

Patent Number

Super Compressor, Screw-in Back, Dual Crown/Single Crown, All Sizes

BREVET 317537
BREVET 337462

Super Compressor, Bayonet Back, Dual Crown, All Sizes

BREVET 314962

Compressor, snap-on back

BREVET 313813