Audemars Piguet Royal Oak Royal Oak Perpetual Calendar Openworked

Reference 26685XT.OO.1320XT.01

About this watch

The Audemars Piguet Royal Oak Selfwinding Perpetual Calendar 26685XT.OO.1320XT.01 debuted in 2026 as part of the Royal Oak collection, introducing the openworked perpetual calendar Calibre 7139 in a titanium and Bulk Metallic Glass (BMG) case configuration. The watch is housed in a 41 mm case crafted from titanium, with the bezel and caseback executed in BMG. Case thickness measures 9.5 mm. Sapphire crystals are fitted on both the dial side and case back. Water resistance is rated to 50 metres. The integrated bracelet is manufactured from titanium with BMG links and secured by a three-blade folding clasp. The dial is executed in sapphire, revealing the movement architecture. It is combined with matching subdials featuring a smoked outer zone and a black inner bezel. The display includes indications for hours, minutes, week, day, date, month, leap year, and astronomical moon. Hands and hour markers are crafted from 18-carat pink gold and filled with luminescent material. Powering the watch is the selfwinding Calibre 7139. The movement operates at a frequency of 28,800 vibrations per hour (4 Hz), consists of 423 components, and contains 41 jewels. It measures 29.6 mm in diameter, has a thickness of 4.1 mm, and provides a power reserve of approximately 55 hours.
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Specifications

Brand
Audemars Piguet
Family
Royal Oak
Model
Royal Oak Perpetual Calendar Openworked
Reference
26685XT.OO.1320XT.01
Movement
ap-7139
Movement Features
  • Hours, Minutes
  • Date, Day, Leap Year, Month, Week Indicator
  • Moonphase
  • Skeleton
Case
41mm
Dial Color
Skeleton
Crystal
Sapphire
Water Resistance
20

Current Listings

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A 37mm Audemars Piguet Royal Oak Self Winding in stainless steel with a blue dial, purchased from an Audemars Piguet Boutique in 2018.

  • Condition: Excellent Condition
  • Bracelet size range: up to 6.75 inches wrist
  • Package type: Complete Packages/Set (double boxes)
  • Papers included: Yes
Posted at
Feb 20, 2025, 10:34 PM
Active
2005 Audemars Piguet Royal Oak 15300ST White Dial - Box and Papers

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The Royal Oak, designed with a 39mm case size that is often worn slightly larger than traditional round watches. The white and steel case provides clean aesthetics, and the integrated bracelet has no slack.

  • Condition: Very sharp
  • Case Size: 39mm
  • Bracelet Type: Integrated
  • Wrist Fit: up to 7.5 inch
Posted at
Feb 20, 2025, 12:03 PM
Active
Audemars PIGUET ROYAL OAK 15510 STAINLESS STEEL BLUE NUIT DIAL 2023 FULL SET

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  • Condition: Excellent, Unpolished Condition
  • Diameter: 41mm
  • Material: Stainless Steel
Posted at
Feb 19, 2025, 10:16 PM
Active
UNPOLISHED CASE MINT 2014 Audemars Piguet 15400ST Royal Oak 41mm with Box & Paper

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A 2014 Audemars Piguet Royal Oak 41mm watch in excellent condition, featuring a stainless steel case and black dial.

  • Condition: Excellent
  • Case size: 41mm diameter
  • Wrist size: 7 1/2 inches
Posted at
Feb 19, 2025, 9:31 PM
Active
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The Audemars Piguet Royal Oak Chronograph features a white Grande Tapisserie dial with three subdials, protected by a glare-proof sapphire crystal. It has an elegant stainless steel case with brushed and polished finishes and an iconic octagonal bezel secured with eight hexagonal screws.

  • Condition: Mint
  • Case size: 41mm diameter
  • Materials: Stainless Steel
  • Water resistance: 50m depth rating
Posted at
Feb 19, 2025, 12:23 PM
Active
Audemars Piguet Royal Oak Offshore Ref. 26405CE

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Audemars Piguet - 26405CE · $26,000
The Audemars Piguet Royal Oak Offshore Ref. 26405CE features a 44mm black ceramic and titanium case, making it a unique addition to any collection.

  • Case material: black ceramic and titanium
  • Size: 44mm
Posted at
Feb 19, 2025, 10:02 AM
Active
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This is an Audemars Piguet Royal Oak Chronograph with a silver dial, stainless steel case and bracelet. The watch features a 38mm case size and has been well-maintained showing only light wear from use.

  • Condition: Excellent
  • Case Size: 38mm
  • Bracelet Length: 19 links
  • Wrist Size Fit: up to 7 inches
Posted at
Feb 17, 2025, 7:24 PM
Active
Audemars Piguet Royal Oak 15450ST White Dial with Box and Papers

Audemars Piguet Royal Oak 15450ST White Dial with Box and Papers

Audemars Piguet - 15450ST · $28,350
This Audemars Piguet Royal Oak 15450ST features a sharp 37mm unpolished case, stainless bezel, and silver grand tapisserie dial with matching original factory hands.

  • Condition: Excellent
  • Case diameter: 37mm
  • Bracelet length: up to 17.5cm / 6.88"
  • Box and papers included: yes
Posted at
Feb 17, 2025, 7:12 PM
Active
Audemars Piguet Royal Oak Double Balance Wheel Openworked 2024 15407ST 41mm

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The Audemars Piguet Royal Oak Double Balance Wheel Openworked is a new, automatic men's watch featuring a steel case with a diameter of 41mm and water resistance up to 5 ATM.

  • Condition: New
  • Case material: Steel
  • Bracelet material: Steel
  • Case diameter: 41mm
Posted at
Feb 17, 2025, 3:11 PM
Active