Audemars Piguet Royal Oak 37 mm 15550ST.OO.1356ST.06 Steel Blue Audemars Piguet Royal Oak 37 mm 15550ST.OO.1356ST.06…

1. What is the Audemars Piguet 15550ST.OO.1356ST.06?
It is the 37 mm stainless steel Royal Oak Selfwinding with Audemars Piguet's blue "Bleu Nuit, Nuage 50" dial in the "Grande Tapisserie" pattern, white gold applied hour-markers and luminescent Royal Oak hands, on a steel bracelet with AP folding clasp. It runs on calibre 5900 and carries the Royal Oak design evolution introduced in 2022.

2. What movement is in the Royal Oak 15550ST?
Calibre 5900, a selfwinding movement with hours, minutes, centre seconds and date. It has 29 jewels and 188 parts, beats at 4 Hz (28,800 vibrations per hour), holds a 60-hour power reserve and measures 26.2 mm across and 3.9 mm thick. It is visible through the sapphire caseback.

3. What is the difference between 15550ST.OO.1356ST.06 and 15550ST.OO.1356ST.02?
Both pair the 37 mm steel case with the "Bleu Nuit, Nuage 50" dial and calibre 5900. The .02 is the 2022 launch version, fitted with the "50-years" oscillating weight that SJX Watches reported only watches produced in 2022 would carry; Audemars Piguet's .06 page lists calibre 5900 without it. The other steel dials are silver-toned (.01), grey (.03 and .07) and light blue (.04 and .08).

4. How is the 15550ST different from the 15450ST it replaced?
The steel 15550 launched in January 2022 at US$24,100, the same price as the outgoing 15450 (SJX Watches). Both are 37 mm with a 60-hour power reserve, but Audemars Piguet lists the 15450ST at 9.8 mm thick with calibre 3120, against 9.1 mm and calibre 5900 for the 15550ST. The newer dial drops the "AP" at 12 o'clock and "AUTOMATIC" at 6 o'clock and gains a solid 24-carat gold applied logo, and the lugs and bracelet taper more. We source the blue 15450ST.OO.1256ST.03 pre-owned from $33,944 (October 12, 2026).

5. How does the 37 mm 15550ST compare with the 41 mm 15510ST?
Both come in steel with the "Bleu Nuit, Nuage 50" "Grande Tapisserie" dial and 50 m water resistance. Audemars Piguet lists the 41 mm 15510ST at 10.5 mm thick with calibre 4302, a 70-hour power reserve and a screw-locked crown; the 37 mm 15550ST is 9.1 mm thick with calibre 5900 and a 60-hour power reserve. We source the blue 15510ST.OO.1320ST.01 brand new from $60,254 (October 12, 2026).

6. How big is the Royal Oak 15550ST and is it water-resistant?
The case is 37 mm across and 9.1 mm thick, with a glareproofed sapphire crystal and caseback, and it is water-resistant to 50 m.

7. How much is the Audemars Piguet 15550ST.OO.1356ST.06?
Bizak & Co. lists it from $52,259 brand new (October 12, 2026), sourced to order; the final price is confirmed with real photos before you pay more than the $200 deposit, which is credited to the price. For comparison, La Côte des Montres lists Audemars Piguet's US suggested retail price at $30,400 (February 2026 tariff), and SJX Watches reported a US$24,100 launch price for the steel 15550 in January 2022.

8. Does the 15550ST.OO.1356ST.06 come with an Audemars Piguet warranty?
Audemars Piguet guarantees its watches against manufacturing defects for 2 years, or 5 years for watches purchased through its authorized network from January 1, 2017, under its International Sales Warranty. The cover left on a sourced watch depends on when it was first sold, so we confirm the warranty card and papers with you, with real photos, before you pay more than the deposit.

9. How do I buy the 15550ST.OO.1356ST.06 through Bizak & Co.?
Reserve with a $200 deposit, credited to the price. After your deposit is verified, we research suitable options and share watch-specific photos and a current quote before you pay the remaining balance; the specific sourced watch is inspected before dispatch under our buyer-protection terms and shipped insured. Box, papers and the final price are confirmed with you before anything more is charged.