Since being founded in 1961, German watchmaker Sinn has specialized in navigation clocks professional pilot watches. And while they do not produce their own movements in-house, they have developed a number of their own technologies, such as: a lubrication free escapement (DIAPAL), an anti-foggin technology (Ar-Dehumidifying) and TEGIMENT (a way of hardening steel to greatly increase scratch resistance).
The Sinn Model 144 St Sa is a pilot chronograph which comes in a 41 mm x 14.5 mm stainless steel case with a bead-blasted matte finish. It features a sapphire crystal in front and back (both with an interior anti-reflective treatment). The case back is secured with screws and the crown screws down. Water-resistance is 200 meters.