2017 Sinn Navigation Chronograph 903 St B E

Historical Context & The Breitling Navitimer Connection:

The story of the Sinn 903 is intrinsically linked to the quartz crisis of the late 1970s. When Breitling faced severe financial distress in 1979, founder Willy Breitling liquidated the company's assets. Helmut Sinn—founder of Sinn Spezialuhren and a former WWII pilot and instructor—saw an opportunity to acquire rights, original design patents, and manufacturing tooling for the legendary Breitling Navitimer.

Rather than copying the design, Sinn legitimately secured the rights to produce the iconic slide-rule navigation chronograph under its own brand name. While Breitling was later resurrected under new ownership, Sinn continued to manufacture and evolve the 903 series. Sinn further enhanced the design by introducing an internal slide-rule bezel operated via a secondary crown at the 10 o'clock position, significantly improving water resistance over the traditional outer-rotating bezel design while preserving full slide-rule navigation functionality.

This example features a deep sunburst navy blue dial, silver sub-dials, and aged ivory faux-patina luminous markers, this iteration (B E standing for Blau/Elfenbein or Blue/Ivory) blends vintage aviation heritage with Sinn’s technical execution.

Condition & Scope of Delivery:

This pre-owned example from June 2017 is in mint condition, displaying crisp case lines, sharp polished chamfers, and original brushed finishing throughout. The sapphire crystal and dial assembly are flawless.

The watch comes as a complete set, including the original Sinn box, signed Sinn guarantee card dated June 2017, and other documentation.

Specifications:

Movement: Automatic Valjoux 7750 base, rhodium-plated with perlage, blued screws, and Geneva-striped Sinn rotor

Functions: Hours, minutes, small sub-seconds, 12-hour chronograph with 30-minute and 12-hour counters, date display at 4:30, internal logarithmic slide-rule bezel

Case Material: Stainless steel, polished and satinized

Case Diameter: 41.0 mm Case Thickness: 14.5 mm Lug Width: 22.0 mm

Crystal: Anti-reflective sapphire crystal front and sapphire display case back

Crown: Screw-down main crown at 3 o'clock; crown at 10 o'clock for operating internal slide-rule bezel

Water Resistance: 10 bar (100 meters / 328 feet)

Dial: Sunburst navy blue dial with electroplated silver sub-dials and ivory-toned luminous hour indices and hands

Luminescence: Ivory-coated Super-LumiNova on numerals, hour markers, and hands

Year of Purchase: June 2017