Product Information
* Factory: ZF Factory
* Brand: Audemars Piguet
* Collection: Royal Oak Jumbo
* Reference: 16202ST.OO.1240ST.01
* Movement: 7121 Automatic Movement
* Crystal: Sapphire Crystal
Technical Specifications
* Case Diameter: 39.0 mm
* Case Thickness: 9.7 mm
* Measured Weight: 132.5 g*
* Movement: 7121 Automatic Movement
* Beat Rate: 28,800 BPH
* Crystal: Sapphire Crystal
*The measured weight of 132.5 g applies to the individual watch inspected in this QC report. Minor differences may occur between individual watches due to bracelet sizing, production tolerances and batch configuration.
Timegrapher Test Results
* Daily Rate: -4 Seconds/Day
* Amplitude: 283°
* Beat Error: 0.4 ms
* Beat Rate: 28,800 BPH
Testing Note
These readings were recorded from this individual watch during its pre-shipment QC inspection.
Mechanical movement performance can vary depending on mainspring power, watch position, ambient temperature and testing conditions. The recorded -4 seconds/day represents the movement’s condition at the time of inspection and should not be interpreted as a permanently fixed daily rate.
For QC evaluation, the daily rate should be considered together with amplitude, beat error and actual movement functionality.
7121 Movement Performance
This ZF Factory Audemars Piguet Royal Oak Jumbo 16202ST.OO.1240ST.01 is equipped with a 7121 automatic movement, operating at 28,800 vibrations per hour.
During this QC inspection, the movement recorded:
* Daily Rate: -4 Seconds/Day
* Amplitude: 283°
* Beat Error: 0.4 ms
* Beat Rate: 28,800 BPH
Under the recorded testing conditions, the movement operated consistently.
In addition to timegrapher readings, automatic winding, manual winding, time setting and date operation should be checked individually before shipment.
Rotor Rotation: Important Characteristic
An important characteristic to understand on this 7121 movement is the behavior of the automatic rotor.
When the watch is moved, the rotor may rotate with a controlled and rhythmic motion rather than spinning continuously or extremely quickly.
Visually, this can sometimes give the impression that the rotor is not moving freely. However, this behavior alone should not be interpreted as the rotor sticking or the movement operating incorrectly.
The key QC point is whether the rotor can correctly operate the automatic winding system.
During inspection, attention should be given to:
* Smooth and rhythmic rotor movement
* Consistent rotor operation
* Normal automatic winding
* No abnormal sticking or resistance
* No contact with surrounding movement components
* No unusual friction during rotation
If the rotor rotates rhythmically and the movement can be automatically wound normally, the rotor behavior does not affect normal operation of the watch.
Automatic Winding Function
Rotor speed alone is not an appropriate way to determine whether an automatic movement is operating correctly.
For this 16202ST, the more useful test is to confirm that the rotor transfers energy correctly to the automatic winding mechanism.
During QC, the watch should therefore be tested after normal movement to confirm that:
* The automatic winding system responds normally
* The movement continues running correctly
* The rotor does not become stuck
* No abnormal resistance develops during rotation
This provides a more meaningful assessment than simply comparing the rotor’s visual rotation speed with a different movement.
A reference video of the actual rotor operation can also be provided so the customer can see its normal rhythmic movement before shipment.
Case Dimensions and Weight
The individual watch inspected measured:
* Case Diameter: 39.0 mm
* Case Thickness: 9.7 mm
* Measured Weight: 132.5 g
The relatively slim 9.7 mm measured thickness is an important physical characteristic of this Royal Oak Jumbo configuration.
The 132.5 g weight is the actual measurement of this individual QC sample. Small variations may occur between individual watches due to bracelet sizing and normal production tolerances.
Sapphire Crystal and Exterior Inspection
The watch uses a sapphire crystal, which should be inspected for clarity, surface condition and correct installation.
Because the Royal Oak design relies heavily on case and bracelet geometry, QC should also pay particular attention to:
* Dial alignment
* Hour-marker positioning
* Hand alignment
* Date-window positioning
* Bezel alignment
* Case edges
* Bracelet articulation
* Bracelet-to-case integration
* Clasp operation
* Overall exterior assembly
These physical details should be inspected on the actual watch rather than judged only by factory name or model specifications.
QC Observations
The ZF Factory Audemars Piguet Royal Oak Jumbo 16202ST.OO.1240ST.01 showed stable movement performance during this pre-shipment inspection.
The 7121 movement recorded -4 seconds/day, 283° amplitude, 0.4 ms beat error and a beat rate of 28,800 BPH.
The individual watch measured 39.0 mm in diameter, 9.7 mm in thickness and 132.5 g in weight.
One point that should be clearly explained before shipment is the rotor behavior. The automatic rotor may rotate in a more rhythmic pattern rather than spinning very rapidly. This should not automatically be interpreted as sticking or poor movement performance.
The important point is that the automatic winding system operates normally and the rotor behavior does not interfere with normal movement operation.
For customers unfamiliar with this characteristic, a video showing the actual rotor movement can provide a clearer reference before shipment.
Pre-Shipment QC Inspection
* ✔️ 7121 automatic movement checked
* ✔️ Timegrapher readings recorded
* ✔️ -4 seconds/day rate documented
* ✔️ 283° amplitude recorded
* ✔️ 0.4 ms beat error recorded
* ✔️ Automatic winding function checked
* ✔️ Manual winding function checked
* ✔️ Rotor rotation inspected
* ✔️ Rhythmic rotor movement checked
* ✔️ Abnormal rotor resistance or sticking checked
* ✔️ Time-setting function checked
* ✔️ Date operation checked
* ✔️ Case diameter measured at 39.0 mm
* ✔️ Case thickness measured at 9.7 mm
* ✔️ Individual watch weight measured at 132.5 g
* ✔️ Sapphire crystal inspected
* ✔️ Dial and hand alignment checked
* ✔️ Bezel and case finishing inspected
* ✔️ Bracelet articulation and assembly checked
* ✔️ Clasp operation inspected
* ✔️ Final pre-shipment QC inspection completed
