Audemars Piguet is widely credited with creating the luxury steel sports watch category, forever changing the watch industry with the introduction of the Royal Oak Ref. 5402 in 1972. At the time of its launch, the Royal Oak was revolutionary, setting new standards in both design and craftsmanship. Today, the Royal Oak is recognized as an iconic design, instantly recognisable for its octagonal bezel, secured by eight hexagonal white gold screws, and its celebrated integrated bracelet.

A standout feature of the Royal Oak is the seamless fusion of its case and bracelet, a design choice that was unprecedented at the time. The bracelet's links are joined by two perpendicular smaller stainless-steel links, which allows the bracelet to curve naturally with the wrist. This design not only creates a striking visual impact but also ensures the watch is as comfortable to wear as it is beautiful to look at.

The steel “B Series” followed the first 2,000 Royal Oaks from the “A Series.” The inaugural A Series was numbered from A 0001 to A 2000, with the first 1,000 pieces selling out quickly. Given the overwhelming success of the model, Audemars Piguet made the decision to increase production to 2,000 pieces.

Once the A Series sold out, the brand continued its production with the B Series, followed by the C Series, and so on, marking the continued rise of the Royal Oak as a coveted luxury watch. The B Series was numbered from B 1001–B 2000, so the B series references are actually rarer that the A series.