Sinn doesn't make watches to look good—they make watches to work. Founded by a pilot and developed in partnership with German special forces, Sinn creates some of the most technically advanced tool watches in the world, built to function in conditions that would destroy lesser timepieces.
Founded by a Pilot, For Pilots
Helmut Sinn was a German flight instructor and pilot who founded his watch company in Frankfurt in 1961. As a pilot himself, Sinn understood exactly what aviators needed from their instruments—reliability, legibility, and precision. He began by creating pilot chronographs using Swiss movements, establishing a reputation for professional-grade aviation watches.
The early Sinn watches were no-nonsense instruments designed for cockpit use. They featured high-contrast dials, large luminous markers, and chronograph functions essential for navigation calculations.
The Lothar Schmidt Era
In 1994, Helmut Sinn sold the company to Lothar Schmidt, an engineer who had previously worked at IWC. Under Schmidt's leadership, Sinn transformed from a respected pilot watch maker into a leader in technical innovation. Schmidt brought an engineer's mindset to watchmaking, developing proprietary technologies that would set Sinn apart.
Schmidt moved the company's headquarters to a new facility in Frankfurt and invested heavily in research and development. The results would revolutionize what was possible in tool watch construction.
Proprietary Technologies
Ar-Dehumidifying Technology: Sinn developed a system using copper sulfate capsules inside the watch case to absorb moisture. This prevents fogging of the crystal in temperature extremes—a critical feature for pilots moving between cold high altitudes and warm ground conditions.
Tegiment Technology: Sinn's proprietary case hardening process makes steel surfaces extremely scratch-resistant by hardening them to 1,200 Vickers—roughly five times harder than conventional stainless steel. A Tegiment-treated watch maintains its appearance through years of hard use.
DIAPAL: This technology uses special oils and lubricants that allow escapement components to run without traditional lubrication on certain parts, reducing wear and extending service intervals.
Magnetic Field Protection: Many Sinn watches feature soft iron inner cases that protect movements from magnetic fields up to 80,000 A/m—essential for pilots and anyone working near electronic equipment.
EZM: Watches for German Special Forces
Sinn's EZM (Einsatzzeitmesser, or "Mission Timer") line was developed in collaboration with German police special forces units. The EZM 1, created with the GSG 9 counter-terrorism unit, had to meet demanding specifications for underwater operations, impact resistance, and reliability under combat conditions.
The EZM series represents the ultimate expression of tool watch philosophy—these aren't styled to look tactical, they're built to survive actual tactical operations. Every feature serves a function; nothing is decorative.
The U-Series: Submarine Steel
Sinn's U-series watches use steel sourced from the same suppliers that provide material for submarine hulls. This German submarine steel is extremely resistant to salt water corrosion and can be Tegiment-hardened for additional scratch resistance. The U1, with its distinctive fully-captive rotating bezel, became one of Sinn's most popular models.
Space-Tested: The 140 S
In 1985, a Sinn chronograph was worn by German astronaut Reinhard Furrer aboard the Space Shuttle Challenger. This space heritage adds to Sinn's credentials as a maker of instruments trusted in extreme environments.
Frankfurt Financial District Watch
In a unique collaboration, Sinn created the 6000 and 6060 models in partnership with the city of Frankfurt's financial district. These watches are only available for purchase at the Sinn store in Frankfurt, creating a direct connection between the brand and its home city.
Sinn Today
Sinn remains independent and based in Frankfurt, producing around 12,000 watches annually. While Swiss brands dominate the luxury market, Sinn has carved out a unique position: the thinking person's tool watch. Their customers tend to be pilots, military personnel, engineers, and collectors who appreciate substance over marketing.
Every Sinn watch is designed to answer a simple question: what does the user actually need? The answer is never "a pretty watch." It's always a more functional one.