Audemars Piguet Royal Oak 26586BA.OO.1240BA.98 Perpetual Calendar RD2 Ultra-Thin Yellow Gold Green Dial Limited Edition of 50

The Audemars Piguet Royal Oak Perpetual Calendar Ref. 26586BA.OO.1240BA.98 “RD2” is one of the most important modern Royal Oaks ever created, combining extreme technical achievement with uncompromising design. Limited to just 50 pieces, this yellow gold execution of the RD2 project represents the thinnest automatic perpetual calendar wristwatch ever produced at the time of its release. Developed under the “Research & Development 2” program, this reference redefined what was mechanically possible within the Royal Oak framework, all while preserving full robustness and everyday wearability.

Crafted entirely in yellow gold, the 41mm Royal Oak case and integrated bracelet deliver unmistakable presence, elevated by the warmth of the metal. The green dial adds a contemporary, unexpected contrast, giving the watch a distinctly modern personality despite its classical complication. The dial layout remains clean and highly legible, with day, date, month, leap year, and moon phase displays arranged harmoniously across the surface. The slimness of the case is immediately apparent on the wrist, allowing the watch to sit flatter and more elegantly than any previous perpetual calendar Royal Oak.

What sets the RD2 apart is its integrated perpetual calendar architecture, designed from the ground up to reduce thickness without sacrificing reliability. Rather than stacking modules, Audemars Piguet engineered the complication directly into the movement, a breakthrough that reshaped high-complication sports watchmaking. For collectors, this reference is far more than a rare Royal Oak—it is a milestone in modern horology. The combination of ultra-thin engineering, precious metal construction, limited production of 50 pieces, and a striking green dial makes the 26586BA a true connoisseur’s watch, occupying a permanent place in Audemars Piguet history.