Introduced in the early 1960s, the Favre Leuba Bivouac represented a groundbreaking innovation in the world of wristwatches, being the first of its kind to integrate both a barometer and an altimeter. Engineered with the rugged demands of mountainous terrain in mind, it stood as a testament to human ingenuity in conquering nature's extremes. This particular model, identified by its reference number 53223, boasts distinctive features that enhance its functionality and aesthetic appeal. A striking blue barometer scale adorns its dial, offering precise atmospheric pressure readings, while silver hour markers, complemented by tritium lume dots, ensure optimal visibility in low-light conditions. Positioned at 6 o'clock, a small second sub-register adds a subtle yet functional element to its design. Moreover, a rotating black bezel (Bakelite?) serves as a reliable indicator of altitude, capable of measuring heights up to 3000 meters above sea level. Beyond its technical prowess, this Favre Leuba Bivouac stands out for its impeccable condition, a testament to its careful preservation over the years. The dial remains pristine, retaining its original integrity, indicative of minimal usage. The unpolished case, characterized by sharp lines and edges, bears clear engraving detailing its purpose as an altimeter and barometer, alongside the reference number 53223. With its captivating black-and-blue dial and functional complications, this last iteration of the first series Favre Leuba Bivouac exudes a timeless charm that transcends generations. Model: 53223 Size: 40mm Material: SS Bracelet/Strap: Canvas