Sinn U18 Limited Edition on H-Link Quick Adjust Bracelet

SKU: SI-0047

Brand: Sinn Watches

About: Sinn North America


New Spring 2025 Release - Limited to 1,000 Pieces

Dive watch with satinized steel case and 2,000 meters WR - 44 mm
• Watch diameter (mm): 44.0
• Watch height (mm): 15.5
• Lug width (mm): 22
• Lug to lug (mm): 50.5
• Weight - head only (grams): 114
• Water resistance: 2,000 meters
• Case back: Solid
• Case finish: Satinized
• Case metal: Decommissioned submarine steel
• Dial color: Blue Green
• Front crystal: Sapphire
• Tegimented: Bezel only
• Inert gas: Filled
• Calibre: SW300-1
• Copper sulphate: Capsule
• Movement: Automatic mechanical
• Strap or bracelet: Bracelet
• Quick adjust buckle: Yes
• Manufacturer's limited warranty: 3 years

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WatchBuys Price: $3,680

Sinn U18 Limited Edition on H-Link Quick Adjust Bracelet
Sinn U18 Limited Edition on H-Link Quick Adjust Bracelet

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Sinn U18 Limited Edition on H-Link Quick Adjust Bracelet
Sinn U18 Limited Edition on H-Link Quick Adjust Bracelet
Sinn U18 Limited Edition on H-Link Quick Adjust Bracelet
Sinn U18 Limited Edition on H-Link Quick Adjust Bracelet
Sinn U18 Limited Edition on H-Link Quick Adjust Bracelet
Sinn U18 Limited Edition on H-Link Quick Adjust Bracelet
Sinn U18 Limited Edition on H-Link Quick Adjust Bracelet
Sinn U18 Limited Edition on H-Link Quick Adjust Bracelet
Product Details

20 Years of German Submarine Steel

The story behind the development of the Sinn U18 Limited Edition is just as cool as the watch itself, and this is a very cool watch.

For 20 years, Sinn's U Series watches have been built using the same special grade of steel as German Naval submarines.  Those submarine steel cases and bezels are built from steel that Sinn receives from ThyssenKrupp, a German engineering company that develops steel for the outer hulls of German submarines. 

Rather than form the case and bezel of this watch from steel meant for submarines, the case and bezel of the new Sinn U18 Limited Edition was formed from a submarine — more specifically, the steel hull of a decommissioned German U18.  The steel used to in this watch has spent decades under the surface roaming Earth's oceans in service of the German Navy. 

To emphasize how special this model is, Sinn has chosen to fully satinize the case, bezel, and bracelet of this watch, a first for any Sinn U Series model.   The unique blueish green bubble dial is complemented by matching blueish green markers around the bezel.

This watch is a limited edition of 1,000 pieces - the limited edition number is engraved on the case back of each piece along with the image of a submarine.



44 mm Submarine Steel Case

The Sinn U18 Limited Edition is housed in a satinized 44 mm case. Sinn U15, U16, U18 PDF

Built by SUG in Glashutte, Germany from German submarine steel, the steel used to create this watch has already traveled nearly 200,000 nautical miles over nearly 40 years as part of the outer hull of a decommissioned German Type 206 submarine — the U18.  

In fact, each watch of this limited edition will be ever so slightly different from the rest.  Small visible marks and subtle variations in the steel are the result of decades of being beaten against by the seas.

Please click on the PDF linked on the right to learn more about the history of the U18 submarine and the origin of this project.



Submarine steel resists the effects of exposure to saltwater and saltwater environments while also being amagnetic, which means that is does not have magnetic properties and cannot itself become magnetized. The watch movement itself is protected from magnetic fields up to 4,800 A/m.  

The uni-directional rotating bezel is also milled from this submarine steel and is Tegimented (hardened). The indices are machined directly into the bezel without the use of bezel inserts, which can corrode or come loose at deep depths.  The color of the bezel markers matches the blueish green hue of the dial. 

The Sinn U18 Limited Edition has been independently tested and certified as water resistant to 2,000 meters. 



A Unique Dial

The underwater look of this limited edition dial is definitely fitting for a watch built with submarine steel.

Sinn describes the color of this glossy dial as dark blueish green with a subtle gradient.  The air bubbles rising from 6 to 12 give the dial a three dimensional look while remaining perfectly smooth.  

The overall color of the dial can appear to change between depending on the lighting conditions, and the "bubbles" really pop in bright light. 

The text on the lower half of the dial commemorates the German U18 submarine.  "KLASSE 206" refers to the type of German U-boat, Type 206, and "192.842" refers to the number of nautical miles traveled by the U18 submarine.



Additional Sinn Technologies

The Sinn U18 Limited Edition features Sinn's "Dry Hold" technology to protect the movement oils, lengthen service intervals and to eliminate crystal fogging. 

Sinn uses a combination of copper sulphate capsules and inert gas to achieve these effects, and the presence of this technology boosts the warranty period to three years.



Important features of this watch include:

  • Blueish green dial with underwater air bubbles design
  • Case and bezel made of decommissioned U18 submarine steel
  • Satinized finish on case, bezel, and bracelet
  • Copper sulphate capsule and inert gas to protect oils and regulate humidity
  • Water resistant to 2,000 meters
  • Low pressure resistant
  • SuperLuminova on the hands and hours (glows green)
  • Slightly domed sapphire crystal with double sided AR coating
  • Limited edition of 1,000 pieces

This watch is fitted with a satinized H-Link steel bracelet with Sinn's new quick adjust buckle.



Sinn Packaging
Special Packaging and Box

When purchasing a Sinn U18 Limited Edition you not only receive an outstanding timepiece, but a few bonus items that are included in the special packaging.  

The watch is presented in an extra wide Sinn box with a strap changing tool, additional spring bars, and a linen drawstring bag containing a submarine steel blank with "U18" engraved into the top.


Sinn U15, U16, and U18 Video







How Can I Purchase This Watch?

This is a brand new model from Sinn and we are now accepting reservations.

If you would like to be among the very first to own this watch, please follow the link below to learn about the reservations process.  Watches will be delivered in the exact order in which we receive your reservation.

To make a reservation and to learn more about delivery estimates please click here.


Watch specifications are provided by the respective watch manufacturer and/or other sources. Although we use best efforts to provide accurate information, we reserve the right to make corrections when advised of specification changes and/or content errors.



WatchBuys is the official and authorized North American distributor and importer for Sinn watches.

When you purchase your new Sinn watch from WatchBuys, you'll not only get a finely engineered timepiece with excellent value for money, but you'll also benefit from the WatchBuys Sinn Advantage.




WatchBuys Advantage #1

Because we are the official and authorized North American Sinn distributor and importer, your name and watch serial number will be automatically registered in our database for a Sinn manufacturer's limited warranty which we pass through.

This means that should your watch require service during the Sinn manufacturer's limited warranty period, service will be provided by Sinn in Germany when you return your watch to them. This Sinn manufacturer's limited warranty is transferable to subsequent owners as allowed by Sinn.

You are responsible for paying the shipping charges to Sinn, and all repairs that Sinn approves under its warranty are at no charge. Sinn will also pay the return shipping charges to the address you specify.

The Sinn manufacturer's limited warranty period is as follows:
  • Watches in the EZM Series: 3 years
  • Watches marked AR containing inert gas: 3 years
  • Watches in the DIAPAL Series: 5 years
  • All other Sinn models: 2 years

WatchBuys Advantage #2

As an added benefit to those who purchase Sinn watches from WatchBuys, you may choose to have your warranty repairs serviced through one of our two US based factory authorized service centers. This added benefit saves our clients the time and effort of returning their watches to Germany for repair. This service is transferable to subsequent owners who purchase directly from the original registered owner.

Please note that you are responsible for paying shipping and insurance charges for sending your watch to our service centers. Once they reach your watch in the service queue they will determine which repairs are covered under Sinn's warranty.

To contact us about service or repairs under warranty please use this link.

It is important to note that oil-filled quartz Sinn watches must be repaired in Germany (EZM 2, Hydro and UX series). If your watch meets one of these conditions and requires service under warranty, please click here for instructions on returning your watch to Sinn in Germany.


WatchBuys Advantage #3

Your watch will be repaired at no cost to you other than shipping charges to either Sinn or our US service centers during the warranty period. Sinn watches purchased through the "grey market" (non-authorized sources) may carry no warranty from Sinn. Sinn watches purchased through authorized overseas retailers are governed by the warranty policies of those dealers and/or Sinn and typically must be sent to either the overseas dealer or Germany for repair.


WatchBuys Advantage #4

You'll be wearing your new Sinn watch soon after your order is placed since we stock Sinn watches and ship free using FedEx.  Plus, since we are located in the United States, there are no "hidden charges" for shipments to US residents as is the case with most overseas dealers. Such charges can add up to 15% to the cost of your new watch, and include credit card surcharges, foreign exchange credit card bank fees, import duties and taxes, and custom's broker charges.


WatchBuys Advantage #5

WatchBuys offers a comprehensive return policy with no restocking fees to US residents. Overseas dealers, including those involved in the grey market, typically don't offer a return policy, and if they do, returning a watch under the policy is both complicated and expensive due to import/export and custom's requirements. Restocking fees are also common and may range up to 15%.

Learn more about our return policies.


WatchBuys Advantage #6

WatchBuys is pleased to accept payments through PayPal, debit and credit cards. We charge no surcharges to use credit or debit cards, and because we are based in the United States your US card is charged in US dollars with no conversion or exchange rate fees.

We also accept payments from PayPal and charge no surcharges.

Please note that to pay by credit card, debit card or PayPal your account and/or card must be issued by US or Canadian financial institution and billed to a confirmed US or Canadian address.


WatchBuys Advantage #7

When you purchase your new Sinn watch from WatchBuys, you'll earn WatchPoint Rewards which accumulate and may be redeemed against future purchases.




Sinn watches feature a number of cutting edge technologies, many of which are unique to Sinn. Please note that not all Sinn watches, including the watch on this page, use all of these Sinn technologies.

Among the more notable Sinn technologies are:


Tegimented Hardened Cases

Many Sinn watches are fitted with Tegimented cases produced in-house by Sinn's case making affiliated company in Glashutte, Germany.

Standard steel used by most watch companies has a hardness of between 200 and 240 HV (Hardness Vickers is a common scale used to measure material hardness). The Tegiment process produces a hardness of at least 1,200 Vickers which is five times harder than standard steel (and on some Sinn models up to nine times harder than standard steel).

The Tegiment process is not a coating consisting of a foreign material; instead the steel itself that has been hardened using a special engineering process that creates a hardened barrier. The base material is a type of stainless steel also used for surgical implants, and the stainless steel resistance to corrosion is further improved by the Tegiment hardening process.

The primary advantages to a Tegimented case are extreme resistance to scratches and other case abrasions, as well as increased resistance to corrosion.

Please note that certain Sinn watches are fully Tegimented (case, bezel) while others are Tegimented only on the bezel. Use the links below to view both categories.

  • View Sinn watches with fully Tegimented cases.

  • View Sinn watches with Tegimented bezels only.


Dehumidification Technology

A number of Sinn models feature cases filled with inert gas. Sinn has found that filling the case with inert gas can help prevent the introduction of moisture and humidity to the case, as well as provide a more stable environment for the oils that lubricate the movement.

The proper care of any mechanical watch movement mandates that these oils maintain both their viscosity and lubrication properties.

  • View Sinn watches with dehumidification technology.


Copper Sulphate Capsules

A number Sinn models use one or more copper sulphate capsules to absorb humidity trapped inside the case. Over time these capsules will gradually turn dark blue indicating that humidity has been absorbed.

The primary benefit to these copper sulphate capsules is a more dry and stable environment for both the movement and the lubricating oils. Together with Sinn's inert gas treatment these capsules form the basis of Sinn's Dry Hold Technology.

This technology not only provides a more stable environment for the movement, but also prevents fogging of the crystal when going from hot to cold environments or from humid to non-humid conditions (such air conditioned buildings).

  • View Sinn watches with copper sulphate capsules.


Extreme Antimagnetic Protection

Magnetism can cause dramatic swings in the timekeeping of a mechanical watch movement. People are often exposed to magnetic fields without even being aware - frequent high altitude flying, metal detectors, audio and video equipment, medical equipment and computer equipment can all cause problems with magnetism.

Many Sinn watches offer extreme protection against magnetism up to 80,000 A/m. Sinn achieves these results using a number of different technologies, including special case and case back construction, soft iron components in the case and protective rings surrounding the movement.

  • View Sinn watches with extreme antimagnetic protection.


DIAPAL Oil Free Escapement

Sinn caused quite a stir when they first released their DIAPAL technology. Beginning in 1995, Sinn began work to create an oil free escapement. With any mechanical watch movement, the aging of oil, especially in the escapement can create long term problems for that movement. Additionally, as movement oil ages, required service intervals become more frequent.

Sinn's early analysis to this problem provided a quick solution (at least in theory) - if you don't use oil, it can't age. The process began by exchanging the ruby escapements for diamonds (the word "DIAPAL" derives from the German name for diamond escapements) in order to achieve the desired effect. The designation stuck, even though today Sinn works with solutions taken from advanced nanotechnology rather than diamonds.

The result is a movement that proves so reliable that Sinn offers an unprecedented five year warranty on their DIAPAL watches.

  • View Sinn watches featuring the DIAPAL oil free escapement.


Hydro Oil Filled Technology

Sinn has developed a technology termed "Hydro" in which the entire watch case is filled with oil. Watches using this technology are based on quartz rather than mechanical movements.

By using this type of movement, Sinn is able to fill the watch with oil, which has the joint affect of greatly enhancing the readability of the dial and time from any angle (including under water), and increasing the water resistance of the watch even at great depths.

  • View Sinn watches with Hydro Oil Filled technology.


Submarine Steel

Sinn has created a line of watches featuring cases made from German submarine steel (the U Series). The steel was procured by Sinn from a steel supplier to Emden GmbH, one of Germany's North Sea shipbuilding yards who construct submarines from the very same steel.

Because of the special steel used from the submarine steelmanufacturer, the case resists the effects of exposure to salt waterand salt water environments.

These cases are produced in-house by Sinn's case making affiliated company in Glashutte, Germany.

This special steel is also amagnetic which means that is does not have magnetic properties and cannot itself become magnetized. The watch movement itself is protected from magnetic fields up to 4,800 A/m.

  • View Sinn watches built from German submarine steel.



EZM Mission Timers

Sinn is a partner for manufacturing watches for the German Special Forces, including SWAT, Customs, FBI, helicopter police, GSG9 and other units.

Beginning with the now highly collectible (and valuable) Sinn EZM 1, Sinn has grown this collection to some of the most durable and highly functional watches made and they remain among the most popular in the collection.

  • View Sinn watches in the EZM Series.