Longines has introduced a high frequency movement that is more accurate than the standard required to pass chronometer testing.
The 5Hz Calibre L836.6, made exclusively for Longines by Swatch Group stablemate ETA, is housed in a modern reissue the Ultra-Chron diver inspired in its design by a 1968 timepiece of the same name.
Longines wants the Ultra-Chron to be rugged and reliable, as well as accurate, and has been made to resist water pressure, scratches and shocks.
Dive watches with the more sinuous, Blancpain Fifty Fathoms-style, bezel with sapphire crystal insert are becoming more common this year.
Longines has used the style in the 43mm steel cushion shaped Ultra-Chron.
It has a utilitarian black grained dial with a white minute track using alternating Super-LumiNova-coated batons and rhodium plated appliques.
It is sold on either a leather strap or a steel bracelet and comes with an extra black NATO strap crafted from recycled material.