We think this watch has attitude. Sinn took all that's great about the best selling Sinn U1 and added an all new black bezel. This bezel has been fully Tegimented to 1,500 Vickers, or more than 7 times the hardness of standard stainless steel.
The black bezel creates a perfect contrast with the submarine steel case, and with the white and red markings is highly legible.
The U1 SDR case is made from the same steel that is also used in the construction of the outer hull of submarines. The steel was procured by Sinn from a steel supplier to Emden GmbH, one of Germanys North Sea shipbuilding yards who construct submarines from the very same steel. 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.
The uni-directional ratchet operated rotating bezel is also milled from this submarine steel and is Tegimented. The indices are machined directly into the bezel without the use of bezel inserts, which can corrode or come loose at deep depths. The international testing lab of Germanischen Lloyd has tested the U1, and determined that the watch can be certified as water resistant to 1,000 meters. This same firm tests submarines for their ability to withstand the effects of underwater use.
Matte black dial with date at 3, Super Luminova on hands and markers, and striking red seconds hand complete the design. Other features include sapphire crystal with anti-reflective coating, and silicone rubber strap with double push deployant buckle and fliplock safety clasp.