The Chronograph 24h is the newest addition to Longines’ GrandeVitesse line. The 44mm case is fitted with the a modified version of the automatic ETA Valjoux 7754 movement made exclusively for Longines, dubbed caliber L686. As you might guess from its name, this new watch incorporates chronograph and second time zone.
The movement, visible through a sapphire display back, runs in 25 jewels at at 28,800 vph with a power reserve of 46 hours. The chronograph features center seconds, a 30 minute counter at 12 o’clock and a 12 hour counter at 6 o’clock. Continuous small seconds are located at 9 o’clock. The second time zone is indicated via a black 24 hour hand with a red triangular tip. The case features a double tachymeter on the bezel, graduated in kph and MPH, that can be used for measuring ground-speeds up to Mach 2. The crown and push-pieces have a non-slip texture. The crystal is sapphire with an anti-reflective coating, and the case is water resistant to 50 meters. The rhodium-plated hands are polished and use Superluminova for visibility after dark. The dial is available in 3 colors: black, dark brown and silver.
The Chronograph 24h is available on a stainless steel bracelet with a triple folding safety clasp ($2550) or on a black or brown leather strap with alcantara lining and a folding clasp ($2350).