The Sinn Einsatzzeitmesser 2 (EZM2)

 

In the late 1990’s Sinn released a new line of watches with the EZM moniker. EZM stands for Einsatz Zeit Messer, which translates to English as Mission Timer.  These watches were designed to be issued as tool watches to the German special police forces and each watch (EZM1 thru EZM4) had different functionality to suit its intended special force’s needs. The range consisted of the custom special combatant (EZM1), the border guard diver unit (EZM2), the police special force (EZM3), and the fire fighting rescue unit (EZM4).  Sinn used different movements (Quartz, Automatic) and different watch styles (Diver, Chronograph) to create this range of tough, non-nonsense watches - in this article we will focus on the EZM2.  

Sinn watches have long been known for their high quality functional watches and reasonable prices. The EZM2 personifies this perfectly. For this timepiece, Sinn decided to build a watch based on their existing 403 model which utilised a quartz movement (ETA 955.612) with 7 year battery life. Needless to say, this helped keep the price affordable, but don’t confuse this as some kind of cheap battery powered watch. The EZM2 is shock resistant and anti-magnetic and the case is filled with pure silicone oil thereby providing optimum visibility at any angle, especially when submerged. The oil also enables the watch to withstand depth pressures that would crush ordinary watches.  Sinn calculate that the watch could withstand depths of 11,000 ft / 5000m, but instead they, and this is typically Sinn, mark the caseback simply with an understated ‘Waterproof’. Make no mistake - this is a tool diver’s watch!

The Stainless Steel case is extremely well made by case maker SUG (Sächsische Uhrentechnologie GmbH Glashütte) which was co-founded in 1999 by Lothar Schmidt who owns Sinn.  Interestingly, Lothar Schmidt owns 74% of SUG now and when SUG was founded, Schmidt owned 24%, Walter Fricker 50% and Ronald Boldt 26%. Schmidt bought Fricker’s share when he left the SUG partnership.  

The light media blasting of the case is the perfect solution to avoid reflections underwater – It is thought sunlight reflections attract sharks and thus shiny watch surfaces should be avoided when diving. The blasting used on this case also seems to be more resistant to scratches and rub marks than other manufacturer’s media blasted finishes. The screw on back is circular grained which seems slightly at odds with the blasted case finish and is engraved slightly offset with the words “EZM2 HYDRO”. Initially this offset engraving seems strange until you realize that to create the EZM2 Sinn essentalliy took a Sinn 403, turned it through 180 degrees and gave it a new dial. Obviously the CNC case back programme was already set up with the word ‘HYDRO’ and it seems Sinn just added the ‘EZM2’ above it. Between the lugs at 12 the ‘SUG’ logo is engraved and between those at 6 is the plug used when filling the case with the silicone oil.  It has been reported that the process of filling the watchcase with the silicone oil takes 20 hours per watch to ensure all the space is filled and no air remains.

One feature of this watch is that the crown that is located on the left side of the case, thereby making wrist movement easier.  This is especially important for divers who need good wrist movement and also need to avoid snagging the crown on debris underwater, such as old lines, nets, etc.  The crown is signed and screws in securely between its guards.

Interestingly the diameter of the watch is 41mm which nowadays lies right on the border between the larger sized watches which are popular today (Panerai, UTS, etc) and smaller sized watches of yesterday (Rolex Submariner etc). This, and the low height of the watch, has the effect of making the watch very wearable in all situations. It is as easy to wear in an office environment under a shirt cuff, as it is on a weekend diving trip.

The EZM2 is available in two bezel styles – it is understood that both are made of a Titanium base.  Both are uni-directional are easy to grip with gloves, as the edge is slightly proud of the case sides, and have 60 clicks. A plain silver colour bezel and a more common diving style black bezel.  Bezel colour and style is a personal choice but most agree that the black bezel suits the watch better. The lume triangle is cemented in from above using a two stage glue and should not  fall out of the bezel. Strap options for the EZM2 were a waterproof sharkskin leather strap, rubber strap (laterlly with a vanilla smell) or metal bracelet in the typical Sinn style.

The design ‘piece de resistance’ of this watch is the Silicone oil that fills the case.  

The oil overcomes two of the problems associated with dive watches; Water Resistance is assured as the watch is sealed so nothing can enter, or escape; and as the oil cannot be compressed (unlike an argon or air filling) the watch can withstand great depths without damage. As the case, movement and associated watch parts form one ‘solid mass’ and as such there is no need to use a big, thick and heavy case like those seen on other tool divers.

The Silicone oil filling of the EZM2 makes the watch difficult to photograph in sunlight as oil and the flat sapphire crystal tends to make the dial seem ‘fuzzy’. However under water this effect is totally removed and the dial instantly takes on a stunning matt black hue. Almost all watches reflect natural sunlight at least one angle when underwater - usually 45 degrees, or more, from the divers line of sight.  The other effect of the oil is that the hands look to float to the edge of the crystal in an almost ‘cartoonish’ fashion.  This allows the time to be read clearly from angles that are not available with other watches

The sapphire crystal is flat without a Cyclops to magnify the red on black date, giving the watch a very clean look. The uncluttered dial is typically Sinn and very easy to read at a glance with the red seconds hand and date numbers in matt red.  This has the effect of distancing these features into the back ground until the user decides to focus their eyes on them.  When underwater due to the colour saturation at depth, this effect is magnified and the Diver sees only the information they need and is not bothered by anything that is not pertinent to the job in hand. The hands and markers are coated in luminous paint but due to having to shine through the oil in the case, luminosity is less bright than other watches.

Even though the more common EZM2 was the ‘Hydro’ version (as written in red on the dial), Sinn also produced a number of limited editions either for, or to commerate, the Maritime Unit of the GSG-9 (Germany’s equivalent to America’s S.W.A.T). The early GSG-9 version had  a small GSG-9 logo and white date wheel at 3 o’clock, and the later small logo models were supplied with the red and black date wheel with the date at 4 o’clock. These later small GSG-9 logo watches seem to be the more coveted EZM2 among collectors. Another collectable variation of the EZM2 was the earliest version of the ‘Hydro’ model with “3H” on the dial, denoting that tritium coating was used on the hands and markers. The final version of the EZM2 was the GSG-9 limited edition version with the no date and a large GSG-9 logo on the dial.  This logo is said to incorporate; at 12 o’clock two lightning bolts; in the center at 3 o’clock a hand grenade; at 4 o’clock a telescopic sight ‘cross-hair’, horizontally between 5 and 7 o’clock is the GSG-9 logo; vertically from 12 to 6 o’clock is a sword; horizontally between 4 and 8 o’clock is a Trident; in the center at 9 o’clock a parachute.  The dial also has the words “GSG 9 - Counter Terrorism -  Sea - Air - Land - Special Operations” around the outer edge, It is too soon to tell if this will become a collectable model but currently most WIS feel that this logo spoils the dial design as it makes the watch less legible and is at odds with the tool design elements of the watch.

The Hydro versions of the EZM2 were supplied in the typical Sinn black leather type inner, and black card outer, Sinn branded box set with operating instructions (CD with later purchases) and warranty card.

The GSG-9 versions were delivered in a special aluminum attaché case box set.  This set would appear to have been available in two iterations; The earlier (supplied with the early versions of the small GSG-9 logo model) came with a bracelet, sharkskin strap, strap change tool, keyring style LED mini flashlight and a Video about the GSG-9. The later (late small GSG-9 logo and all large GSG-9 logo’d dials) version used the same attaché style case and the set included a GSG-9 DVD, LED flashlight, jackknife, bracelet and sharkskin strap and a strap change tool.

 

The Hydro version of the EZM2 was originally available in two variations at point of sale – either with strap (rubber or leather/shark) strap or with a bracelet.  Both the bracelet and strap (rubber or shark leather) are still available from Sinn. The bracelet is a great fit to the case and is smooth and easy to adjust. The later versions had solid end-links and screw links to size the bracelet.  The clasp has three additional micro adjustments and the divers-extension folds nicely into the clasp when not in use. The clasp feels solid and features a safety lock to prevent opening although, like all Sinn bracelets, it does not have an indent for your thumb nail to aid opening, which seems at odds with Sinn’s functional design ethos.

Specifications:

 

•    Sinn catalogue number starts with ‘403.{serial number of the watch}’

•    ETA 955.612 quartz movement

•    Quick-set date

•    Shock-resistant

•    Anti-magnetic

•    Pure Silicon-oil filled case with membrane at rear to allow for temperature-compensation

•    Extreme readability underwater from any angle due to the oil-filling

•    Left side crown prevents snagging and allows easier hand movement

•    Media-blasted stainless steel case

•    Sapphire crystal

•    Uni-directional elapsed time bezel

•    Luminous hands and markings

•    Water Resistant to practically any depth

•    Stainless steel bracelet with safety lock and a divers-extension.

 

Dimensions:

 

•    Width is 41 mm excluding crown

•    45 mm including crown

•    Lug to lug 47 mm

•    Thickness is 11.4 mm

•    Weight of watch head is 70grammes

 

 

Movement Specifications:

 

•    Type - ETA 955.612 quartz movement

•    Size - 25.6mm (11 ½ Lignes), height 4.5mm

•    Battery CR2016 - Lithium battery with a 7 year life.

•    Hands Min .70, Hr 1.20, Sec .20

•    7 jewels

•    Anti magnetic to German DIN standards

 

Deskdivers feel Sinn made a mistake to discontinue selling the EZM2 when the EZM2-B (or UX) model was released. The case size, form factor with left side crown, the high quality fit and finish and the cool silicone oil filling make this watch a highly usable tool dive watch. It is very comfortable to wear for all occasions and is great value for money. However, it is likely that Sinn, as a small company, simply could not justify having these two series run side by side and decided to move to the larger sized U series watches. Maybe mention the possibility of limiting numbers because of the additional work required to change the batteries could have an impact on Sinn’s service dept? Im not sure that’s true tho… especially as the new UX that replaced it is the same technology…and they still sell the 403…

 

Due to the oil filled case changing the battery in these watches should not be attempted at home, or even by the local battery change kiosk, instead the watch will need to be returned to Sinn in Germany.  At that time Sinn also undertake to replace the dial and hands as the silicone oil is corrosive to the luminous material and after the life of a battery (approx. 7 years) the luminous properties will be past their best.  One issue with this is that the early, and hence collectable, ‘3H’ marked dial is often replaced with the later non-3H marked dial. It is understood that this earlier dial is now discontinued and Sinn may leave the original 3H dial on the watch during the battery service only by special request.

 

Being aware of the lengths Sinn has gone to avoid any air being trapped in the watchcase owners were alarmed by the presence of a bubble in the oil at some angles and on some occasions.  Members of the Watchuseek Sinn forum who were concerned about this bubble contacted Sinn who made the following response:

More information and the history of the GSG-9 can be found here: