Audemars Piguet Royal Oak lll ref.4100St with Papers from 1978

Designed by Jacqueline Dimier and presented in 1977, the Royal Oak 4100 is also known as the Royal Oak III in the archives because it represents the third model in the collection, succeeding the 5402 and 8638.

It was the first Royal Oak to be equipped with a centre seconds hand, and its aim was to win over a clientele that considered the 5402 (39 mm) to be too large, particularly in Italy, the United States and Asia. The 4100 set the standards with a diameter of 35 mm. Right from its introduction, it was available in steel, yellow gold and two-tone versions. The majority of the models were equipped with Calibre 2123, but some of the later creations were powered by Calibre 2125 and others by Calibre 2124. From 1982 onwards, at least 96 watches had their mechanical calibre replaced by quartz Calibre 2506, which was originally fitted in at least 36 watches.

More than 8,400 were produced between 1977 and 1985 and sold until 2002, during which time 2,721 pieces were made in steel, 3563 in bimetal, and 2130 in this yellow gold

Brand: Audemars Piguet
Model: Royal Oak
Reference: 4100st
Year of Manufacture: 1978
Serial Number: N.2xx 
Material: Steel
Dimensions: 36mm
Crystal Material: Sapphire
Luminous Material: Tritium
Movement: Automatic
Length: 18.5cm 
Box/Papers: original papers included
Mechanical Functioning Warranty: 6 months

Comments: Watch is unpolished, mostly unworn with very light scratches. Service crown.