The Navigation Chronograph 903 St II A Watch

The Watch

The Sinn 903 - a true instrument for precision enthusiasts and style lovers alike - features a round design with a 316L stainless steel case. Known for its strength and durability, this material gives the watch a look that is both rugged and refined. At 41 mm in diameter and 14.5 mm thick, it sits beautifully on contemporary men's wrists. The bidirectional rotating internal bezel, fitted with a slide rule, enables quick, on-the-fly calculations - a testament to the functional design built for aviation professionals on the go. Every detail of the case reflects refined aesthetics, with a finish that combines matte brushed surfaces with high-polish accents, further elevating the natural elegance of this horological marvel. The dial is protected by a domed sapphire crystal with double anti-reflective coating, ensuring impeccable legibility in any lighting condition.

The Dial

The dial of this watch is a perfect showcase of fine watchmaking mastery. In gray, it is enhanced by a sunray finish that beautifully catches the light. With well-positioned Arabic numerals and clearly marked indices, reading the hours and minutes is effortless. The minute track running along the periphery not only ensures precision when timing short intervals but also adds to the technical aesthetic of the dial. Luminescent hands deliver excellent legibility in low light, giving this timepiece a striking nocturnal appeal. The dial houses three sub-dials, with a chronograph function enabling precise measurements across 12 hours, 30 minutes, and a small seconds counter. A discreet date window integrates seamlessly into the overall layout, adding an essential everyday function for the modern wearer. Sophistication and function come together here in perfect harmony.

The Movement

At the heart of this watch beats a high-end Swiss automatic movement signed by La Joux Perret. The LJP L110 caliber delivers remarkable precision at a frequency of 28,800 vph, along with outstanding long-term reliability. What sets this movement apart is its impressive 60-hour power reserve, so you never have to worry about the watch stopping on days it's not worn. The stop-seconds mechanism allows you to set the time with absolute precision.

The Strap

This watch comes with two elegant strap options. The first is crafted in gray stainless steel, matching the case for a cohesive look that blends durability with modern style. Its finish combines polished and brushed surfaces, creating an appealing visual contrast and a comfortable feel on the wrist. This bracelet features a deployment clasp, keeping your watch securely in place while making it easy to put on and take off. For those who prefer a more classic, refined look, a black crocodile-embossed calfskin leather strap is also available, adding a sophisticated touch to the ensemble. This leather strap comes with a pin buckle closure - equally practical and stylish - ensuring a personalized fit and a timeless look. The 22 mm lug width makes strap swaps easy and allows you to adapt the watch to your personal style.

Water Resistance

Built for the modern adventurer, the Sinn 903 offers impressive water resistance up to 20 ATM - that's 200 meters deep - making it perfectly suited for nautical activities such as diving, yachting, and swimming. Thanks to its screw-down case back and screw-down crown, this watch delivers optimal protection against water ingress, ensuring both the precision and longevity of its movement.