The AP 15450 and AP 15400 are two of the most-cloned Royal Oak references in the world — the 15450 at 37mm and the 15400 at 41mm. Both share the same Caliber 3120 movement, the same tapisserie dial design, and the same integrated bracelet architecture. They were discontinued in 2019 and replaced by the 15500, but their replica market remains strong because the 37mm size fits smaller wrists and because the 15400 is often considered the classic Royal Oak silhouette. This guide compares the two references directly, covers sizing and wrist fit, and lays out current factory quality and pricing. If you are new to AP replicas, read the complete Audemars Piguet replica guide first.
Key Takeaways
- The 15450 is 37mm; the 15400 is 41mm. Both share the Caliber 3120.
- The 15450 fits wrists under 6.5 inches; the 15400 fits 6.5–7.5 inches and above.
- APS leads 15450 production; ZF and APS both lead for the 15400.
- Prices: $450–$600 for 15450, $550–$750 for 15400.
- Rose gold adds $150–$300 over steel.
- Genuine 15400ST trades $35,000–$50,000; 15450ST trades $28,000–$40,000.
- Both references were discontinued in 2019 — replaced by 15500, then 15510.
What Is the AP 15450?
The AP 15450 is the 37mm version of the Royal Oak, introduced in 2012 alongside the 41mm 15400. It shares the same design language: octagonal bezel with eight visible screws, integrated bracelet, and tapisserie dial.
Its distinguishing feature is size. At 37mm, the 15450 is 4mm smaller than the 15400. It wears similarly but with less wrist overhang and a lighter overall presence. It uses the same Caliber 3120 as the 15400 — a 60-hour automatic movement with a solid gold rotor on genuine examples.
The 15450 was popular in the Japanese and Asian markets where smaller case sizes are preferred, and it is sometimes called the “Asian Royal Oak.” It is a unisex watch — not a ladies model.
The full reference for the most common configuration is 15450ST.OO.1256ST.01 (steel case, silver dial, steel bracelet).
What Is the AP 15400?
The AP 15400 is the 41mm Royal Oak that replaced the 15300 in 2012. It is the reference most buyers picture when they think “Royal Oak” — the classic proportions of the Gérald Genta design at modern scale.
Its most common configuration is 15400ST.OO.1220ST.01 — stainless steel case, silver-toned dial, stainless steel integrated bracelet. Variants include the 15400OR (rose gold) and the 15400SR (steel and rose gold two-tone).
The 15400 uses the Caliber 3120, running at 28,800 vph with a 60-hour power reserve. It was discontinued in 2019 and replaced by the 15500, which uses the newer Caliber 4302 with a central seconds hand.
For the current 41mm reference, see the AP Royal Oak replica guide.
15450 vs 15400: Direct Comparison
| Metric | 15450 | 15400 |
|---|---|---|
| Diameter | 37mm | 41mm |
| Thickness | 9.8mm | 9.8mm |
| Lug-to-lug | 43mm | 47mm |
| Movement | Caliber 3120 | Caliber 3120 |
| Power reserve | 60h | 60h |
| Water resistance | 50m | 50m |
| Years made | 2012–2019 | 2012–2019 |
| Wrist size | Under 6.5 in | 6.5–7.5+ in |
| Replica price | $450–$600 | $550–$750 |
The two references are physically identical apart from case diameter and lug-to-lug. Both use the same movement, both have the same 9.8mm thickness, and both feature the same 50m water resistance rating (though replica water resistance is not guaranteed).
Dial Variations
Both references were offered in multiple dial colors over their production runs. The most common in the replica market:
15450 dials:
- Blue — the signature Royal Oak color, with a sunburst finish
- Grey — subtle, versatile
- Silver/white — the classic configuration
- Black — less common in genuine, but available in replicas
15400 dials:
- Blue — the most-requested color, with a slight premium
- Black — the safest choice for a first replica
- White/silver — the classic 15400ST.OO.1220ST.01 configuration
- Grey — the 2018 “grey dial” edition
- Salmon/copper — rare, higher price
Dial color affects price by 10–15%. Blue and green carry the largest premium. Black and white are the safest for accuracy — cheaper replicas get them right more often.
Movements in 15450 and 15400 Replicas
Both references use the same movement on genuine and in the top-tier replica market: the Caliber 3120.
Three tiers of replica movement exist:
- Asian ETA 2824 clone — used in mid-tier replicas. Runs at 28,800 vph, ~40h power reserve. Decorated to look like the 3120 but with a different bridge layout and balance position.
- Decorated A3120 — a 2824 with cosmetic bridges that mimic the 3120 appearance. High-tier replicas use this.
- Genuine-clone 3120 — the top tier. Found in APS and ZF super clones. Matches the genuine 3120 architecture: 3 visible bridges, balance at 6 o’clock, solid rotor with correct engraving.
To verify which movement is in a specific watch, see the AP super clone guide for identification methods.
The 15450 and 15400 do not use the Caliber 4302. That movement arrived with the 15500 in 2019 and has a central seconds hand — the 15400’s seconds hand is at 6 o’clock. If a seller claims a 15400 has a clone 4302, the watch is mislabeled.
Case Sizes and Wrist Fit
The 15450’s 37mm case and the 15400’s 41mm case feel very different on the wrist, even though both share identical thickness.
| Wrist Size | Best Choice | Reasoning |
|---|---|---|
| Under 6.0 in | 15450 | 15400 overhangs |
| 6.0–6.5 in | 15450 | 15400 is on the edge |
| 6.5–7.0 in | Either | 15450 is subtle, 15400 is classic |
| 7.0–7.5 in | 15400 | Proportional fit |
| Above 7.5 in | 15400 | 15450 looks undersized |
The 15450 is often chosen by buyers who want the Royal Oak design language but prefer a smaller profile — it is popular in professional settings where a 41mm watch feels conspicuous. The 15400 is the default for anyone who wants the “classic” Royal Oak presence.
For the larger current 41mm reference, see the AP Royal Oak replica guide.
Factory Quality: APS, JF, ZF
| Factory | 15450 | 15400 | Notes |
|---|---|---|---|
| APS | Excellent | Excellent | Best dial accuracy, best bracelet fit |
| ZF | Not produced | Excellent | Best 41mm finishing |
| JF | Good | Good | Value tier, older references |
APS leads for the 15450 because the factory invested in the 37mm case tooling. ZF does not currently produce the 15450 — buyers looking for the smaller reference should go with APS or JF. For the 15400, both APS and ZF produce excellent super clones; ZF has slightly better case finishing, APS has slightly better dial printing.
For a broader factory comparison, see the factory comparison in the complete AP replica guide.
Price Guide 2026
| Reference | Factory | Movement | Price |
|---|---|---|---|
| 15450ST Steel Blue | APS | Clone 3120 | $450–$600 |
| 15450ST Steel Grey | APS | Clone 3120 | $450–$600 |
| 15450ST Steel Silver | JF | Clone 3120 | $400–$550 |
| 15400ST Steel Blue | APS | Clone 3120 | $550–$700 |
| 15400ST Steel Black | ZF | Clone 3120 | $550–$750 |
| 15400ST Steel Silver | ZF | Clone 3120 | $550–$700 |
| 15400OR Rose Gold | APS | Clone 3120 | $700–$900 |
| 15400SR Two-Tone | ZF | Clone 3120 | $650–$850 |
Rose gold versions add $150–$300 over steel. Blue and green dials add $30–$80 over black or white.
Care and Maintenance
The 15450 and 15400 replicas require the same care as any Royal Oak replica:
Do:
- Wipe the case and bracelet with a soft cloth after wear.
- Clean the bracelet every few months with mild soap and warm water.
- Service the movement every 4–6 years.
- Store in a watch box to prevent bracelet deformation.
Don’t:
- Submerge in water — most replicas are 3ATM rated, not the 50m genuine rating.
- Expose to strong magnetic fields.
- Attempt to adjust the movement yourself.
For broader care guidance, see the complete Audemars Piguet replica guide.
Conclusion
The AP 15450 and 15400 are the two most-replicated Royal Oak references of the pre-2019 era. Both share the Caliber 3120, both use the same tapisserie dial design, and both are available from APS at super clone tier. The 15450 (37mm) is the choice for wrists under 6.5 inches; the 15400 (41mm) is the standard for 6.5 inches and above.
In 2026, prices run $450–$600 for a 15450ST super clone and $550–$750 for a 15400ST. Rose gold versions add a premium. If you want the current 41mm reference instead, see the AP Royal Oak replica guide for the 15500 and 15510.
Keep reading:
- Complete Audemars Piguet replica guide — the pillar
- AP Royal Oak replica guide — full reference breakdown
- AP super clone guide — movement identification
- AP skeleton replica guide — openworked Royal Oaks
- Best AP replica factories — factory comparison
- How to spot a fake vs real AP — inspection methods
Browse current 15450 and 15400 replicas in the Royal Oak collection — including the 15450ST Grey 37mm, the 15450ST Blue 37mm, the 15400OR Rose Gold, and the 15400OR Rose Gold 41mm.
For the 15450 and 15400’s successors, see Why Are Audemars Piguet Watches So Expensive?.
Authoritative external sources:
