The Aquanaut marked the beginning of a new generation of luxury sports watches for Patek Philippe, inspired by the unmistakable lines of the Nautilus. In 1997, the manufacture introduced the ref. 5060, which was followed a few years later by the ref. 5066, which added an open caseback to the original design. Housed in a yellow gold case with complementary, patinated indices, this paradoxical precious metal sports-watch is all the more intriguing.