Piaget’s first ultra-thin mechanical movement, launched in 1957, was the 9P.
Piaget introduced the manually wound 9P calibre at the Basel watch fair in 1957. Measuring approximately 2 millimetres thick, it helped establish the company’s reputation for elegant, slim mechanical watches. Its compact construction made it particularly suitable for dress watches and helped Piaget distinguish itself in high-end watchmaking.
The 9P is often confused with Piaget’s 12P, which followed in 1960 and became one of the earliest ultra-thin automatic movements. The 9P was manual-winding; the 12P added automatic winding through a miniature micro-rotor. Later Piaget movements, including the 430P, developed the same ultra-thin tradition but were not the original 1957 calibre.