Longines “Agassiz”

European Watch Clock and Jewellery Fair 1986 BF 320
These watches can be safely immersed in water to a depth equal to 10,000 times their thickness In fact, they measure only 3 mm from front to back and are water-resistant to 30 m. This performance is due to a series of technological achievements : a mere 1.5 mm thick quartz movement, a sapphire crystal hollowed out at its centre to allow the passage of the hands, a special copper and beryllium alloy to produce a 0.2 mm thick dial. Available in 18K gold. (LONGINES “Agassiz”)