857 Flieger Steel Watch

Series 857: pilot's watches with protection against magnetic fields.

The Watch
Topped with a flat double anti-reflective sapphire crystal, the round case is crafted in stainless steel. It measures 43 mm in diameter, 12 mm thick, and weighs 90 grams without the strap. The black dial features luminescent white hands, Arabic numerals, and indexes, along with a date aperture at 4 o'clock. The screwed case back is nickel-free. The crown at 3 o'clock is also screwed.

The case is fitted with a black bidirectional rotating bezel that provides a visual countdown function. To prevent accidental rotation, the bezel is secured to the case in such a way that it cannot be lost.

This watch features a black PVD-coated steel bracelet with a deployant buckle. It is water resistant to 20 atmospheres (200 meters) and suitable for swimming and scuba diving.

Specific Technical Features
The case, bezel, and entire steel bracelet have undergone TEGIMENT anti-impact treatment. This surface-hardening technology provides highly effective protection for stainless steel against scratches.

This watch also features Sinn's patented Ar dehumidification technology. This technology slows down the aging process of the watch's internal components, extending the movement's lifespan. It also prevents condensation from forming on the crystal during sudden temperature changes.

It also provides protection against magnetic fields up to 80,000 A/m, thanks to a dial and a double case back made of soft magnetic material. This structure prevents the watch from being disrupted or stopped when exposed to magnetic fields produced by, for example, electric motors or loudspeakers.

The Movement
This watch houses a Swiss Sellita SW300-1 automatic movement. This 25-jewel caliber displays hours, minutes, seconds, and the date through an aperture. It features a Stop Seconds device for precise time-setting to the second. This movement runs at a frequency of 28,800 bph, with a power reserve of 42 hours.