Audemars Piguet Royal Oak Royal Oak Perpetual Calendar Openworked

Reference 26685XT.OO.1320XT.01

Audemars Piguet Royal Oak Perpetual Calendar Openworked

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

Current Listings

Audemars Piguet Royal Oak Offshore Selfwinding Chronograph Ceramic Rose Gold Grey Dial 44mm Box & Papers 26405NR.OO.A002CA.01

Audemars Piguet - 26405NR.OO.A002CA.01 · $42,495

A 44mm rose gold and black ceramic Audemars Piguet Royal Oak Offshore Selfwinding Chronograph with a smoked grey dial, available in like new condition.

Condition: like new
Case size: 44mm diameter
Movement type: Mechanical (Automatic)
Water resistance: 100M (10ATM)

Posted at

May 15, 2026, 7:58 AM

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AP Royal Oak Offshore 1000 series SS bracelet UK

Audemars Piguet - 1000 series

The seller is listing an Audemars Piguet Royal Oak Offshore 1000 series stainless steel bracelet watch, likely from a reputable source.

Uk only: seller's preferred location for sale and shipping
Meets included: includes original paperwork or accessories

Posted at

May 13, 2026, 8:54 AM

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MINT Audemars Piguet Royal Oak Offshore Diver 15710ST 42mm

Audemars Piguet - 15710ST · $16,900

2015-2021 stainless steel Royal Oak Offshore Diver with a black dial, running strong and all functions working as they should.

Condition: MINT
Case size: 42mm diameter
Dial color: black

Posted at

May 12, 2026, 12:38 PM

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2012 Audemars Piguet Royal Oak Offshore 26400AU.OO.A002CA.01

Audemars Piguet - 26400AU.OO.A002CA.01

Posted at

May 11, 2026, 10:19 PM

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Audemars Piguet Royal Oak Offshore Limited Edition 26290RO.OO.A001VE.01 ♦️Lightly Used 2010♦️

Audemars Piguet - 26290RO.OO.A001VE.01 · $36,200

This Audemars Piguet Royal Oak Offshore Limited Edition is a lightly used model from Q4 2010, featuring the Calibre 65 movement and coming with its full set of box and papers.

Condition: Lightly Used
Year: 2010
Case size: 40mm diameter
Calibre: Calibre 65

Posted at

May 11, 2026, 4:49 AM

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Audermars Piguet Royal Oak Offshore “Safari” 26170ST.OO.D091CR.01 42mm Stainless Steel Full Set w/ Both Straps

Audemars Piguet - 26170ST.OO.D091CR.01 · $19,850

A highly collectible 'Safari' edition from the Royal Oak Offshore line, featuring a rugged stainless steel case and a warm ivory dial.

Condition: Excellent Pre-owned condition
Case size: 42mm diameter
Year of production: 2008
Movement: AP's In-House Calibre 3120 Automatic Self Winding Chronograph

Posted at

May 11, 2026, 12:06 AM

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Audemars Piguet Royal Oak Chronograph Blue Dial 26320ST

Audemars Piguet - 26320ST · $45,000

This is a blue dial Royal Oak Chronograph with a 41mm x 11mm case and a 52mm lug to lug. It features an automatic movement, chronograph function, date window with quickset, sapphire crystal, and 50M water resistance.

Condition: Very Good (VG), minor signs of use on the case, minor patina/discoloration around the subdials
Case dimensions: 41mm x 11mm
Lug to lug: 52mm
Movement: Caliber 2385 automatic movement, 40 power reserve

Posted at

May 9, 2026, 3:03 PM

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Audemars Piguet Royal Oak Offshore Bleu Nuit Nuage 50 Beige Dial 43mm 26420CD.OO.A029VE.01

Audemars Piguet - 26420CD.OO.A029VE.01 · $86,995

This watch features a beige dial with blue sub-dials and ceramic bezel, set against the bold Offshore silhouette.

Condition: Brand new
Case size: 43mm
Dial color: beige
Movement caliber: Calibre 4401

Posted at

May 9, 2026, 8:18 AM

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Audemars Piguet Royal Oak Offshore Diver Stainless Steel Grey Dial 42mm 15720ST.OO.A009CA.01

Audemars Piguet - 15720ST.OO.A009CA.01 · $25,395

The Audemars Piguet Royal Oak Offshore Diver is a rugged evolution of the Royal Oak DNA, built for 300m of depth without breaking a sweat. It features a grey 'Méga Tapisserie' dial and an in-house Calibre 4308 visible through the sapphire caseback.

Condition: Excellent
Case size: 42mm diameter
Water resistance: 300m (30 ATM)
Movement caliber: 4308

Posted at

May 9, 2026, 8:17 AM

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