The Sinn 140/142 & 141S chronographs have been worn during several space missions since 1985, when German astronaut Reinhard Furrer wore a black PVD Sinn 141S automatic chronograph during the space mission Spacelab D1 (STS-61-A). Spacelab D1 became more significant later on as the Space Shuttle Challenger sadly got destroyed in its next mission.

• Ref: 141S
• Diameter: 43.00 mm
• Thickness: 15.00 mm
• Lug width: 22.00 mm
• Caliber: Lemania 5012

Interestingly for a long time watch enthusiasts thought that the 140S was the first automatic chronograph was in space. Until 2007 to be precise, when it was finally discovered that it was Colonel William Pogue's personal Seiko 6139 that was the first automatic chronograph in space in 1974. Nevertheless the Sinn 140/142 automatic chronograph has stolen the hearts of many collectors interested in watches used in space and is highly sought after. 

• Ref: 140/142
• Diameter: 43.00 mm
• Thickness: 15.00 mm
• Lug width: 22.00 mm
• Caliber: Lemania 5100

Moreover, Sinn 140/142s were used in during other space missions later on: they were worn on Space Station Mir in 1992 and during Spacelab D2 in 1993 aboard Columbia. It's been reported that those automatic chronographs performed flawlessly even in harsh environments. This historical significance and reliability means that the Sinn 140/142 can be seen as a great Omega Speedmaster alternative.

• Ref: 140b (GMT)
• Diameter: 43.00 mm
• Thickness: 15.00 mm
• Lug width: 22.00 mm
• Caliber: Lemania 1341