In creating the Sinn 556 I, Sinn's goal was to offer their most affordable watch in the line, while at the same time maintaining the quality and engineering standards that have set Sinn apart.
The Sinn 556 I features a case size at 38.5 mm which is satinized. This finish results in a slightly more polished look without the shiny "mirror look". In addition, the dial used for the Sinn 556 I features indices ("I") rather than Arabic numerals for a very clean layout.
Other features of the Sinn 556 I include:
- Case in 316L surgical stainless steel which is satinized
- Sapphire crystals on both sides of the watch
- Double coated anti-reflective covering
- Dual seal crown lock to improve water resistance
We love the Sinn 556 I, and feel that it offers outstanding precision and engineering at an attractive price.
This watch is fitted with a Sinn black calf leather strap with white stitching and tang buckle. Water resistant to 200 meters.
Sinn watches feature a number of cutting edge technologies, many of which are unique to Sinn. Among the more popular features 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 layer has a hardness of 1,200 Vickers which is five times harder than standard steel (and on some Sinn models even higher - up to nine times harder than standard steel).
The Tegiment layer 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 even further improved by the Tegiment hardening process.
The primary advantage to a Tegimented case is extreme resistance to scratches and other case abrasions.
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.
A number of Sinn models feature cases filled with inert gas. Sinn has found that filling the case with 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.
Another advantage to this technology is that it prevents the dial and crystal from fogging. The proper care of any mechanical watch movement mandates that these oils maintain both their viscosity and lubrication properties.
Copper Sulphate Capsules
- View Sinn watches with dehumidification technology.
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).
Extreme Antimagnetic Protection
- View Sinn watches with copper sulphate capsules.
Magnetism can cause dramatic swings in the timekeeping of a mechanical watch movement. People are often exposed to magnetic fields without even knowing so – frequent high altitude flying, metal detectors, audio and video equipment, medical equipment and computer equipment to name a few.
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.
DIAPAL Oil Free Escapement
- View Sinn watches with extreme antimagnetic protection.
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, "Diamantpaletten”) 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.
Hydro Oil Filled Technology
- View Sinn watches featuring the DIAPAL oil free escapement.
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, and each movement is a certified chronometer.
By using this type of movement, Sinn is able to fill the watch with oil, which has the double 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.
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.
EZM Mission Timers
- View Sinn watches built from German submarine steel.
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.
TESTAF Certified Pilot's Watches
Lothar Schmidt, Sinn's CEO and owner had long been disturbed by a lack of technical standards for defining a "pilot's watch". As an engineer, Mr. Schmidt was fluent in standards for diver's watches, anti-magnetic watches and the many other technological standards used to manufacture watches.
A widely used reference for standards is DIN, or the Deutsches Institut fr Normung (German Institute for Standardization). Oddly, he discovered there were no DIN standards to cover pilot's watches where such standards exist for example for diver's watches.
The new "Technical Standard for Pilot's Watches" (TESTAF) was developed by the Aachen University of Applied Sciences and establishes the suitability for professional use as a pilot's watch.
- View Sinn watches in the TESTAF Series