Steel, diamond & rubber watch © Audemars Piguet
Came out in: 1972.
Particular features: The octagonal dial. Its bezel and back are fastened by eight visible screws in grey gold.
Gerald Genta, the designer of the Royal Oak, was inspired by a Navy boat whose hull was made of oak, reinforced with steel, and equipped with octagonal cannon ports.
But the real revolution comes from the use of steel: for the first time in watch-making, an ordinary metal was used in the same way as a precious metal.