The Patek Philippe 5261R – Aquanaut features a mechanical movement with automatic winding, Caliber 26‑330 S QA LU, and includes an annual calendar with day, month, date, and moon phase indicators. Its blue-grey dial with an embossed Aquanaut motif and applied gold numerals with white luminous coating is housed in a rose gold case (39.9 mm diameter, 10.9 mm height) with water resistance to 30 meters and a sapphire crystal case back. Completing the look is a blue-grey composite material bracelet with a patented folding clasp, offering a blend of elegance and functionality.