If you are considering a Jaeger-LeCoultre Rendez-Vous Moon Phase and a listing cites reference 240, treat that number as a question to ask rather than a promise. The purchase should rest on three things you can verify before money moves: the movement inside the case, the actual materials of the case and dial, and the paperwork that ties the watch to a real retail history. A listing described as a replica cannot answer any of those three, no matter which factory name or batch code is attached to it. Buy the documented watch, or walk away and keep looking.
What 240 Typically Refers To
In this collection, numbers appear in three different roles and sellers blend them. A calibre number identifies the movement architecture. A case reference identifies the specific configuration of size, metal, and bezel. A seller code is internal shorthand and carries no meaning outside that seller's inventory. Before you compare two watches, ask the seller to state in writing which of the three they mean by 240. If the answer changes between messages, the listing is not stable enough to bid on.
What to Look For Before You Commit
- Movement identification: calibre number, jewel count, and whether it is automatic. A moon phase is driven by a dedicated gear train, so the movement matters more here than on a plain three-hand watch.
- Case and bezel: measured diameter in millimeters, lug width, thickness, and whether any diamond setting is factory or aftermarket. Aftermarket setting changes the value and the service path.
- Moon phase accuracy: an accurate mechanism tracks the 29.53-day synodic month and drifts roughly one day every two to three years. Large drift over a short period points to a decorative disc rather than a real complication.
- Dial execution: printed text alignment, applied markers, and the finish of the moon aperture. Photographs should be of the actual watch, not catalog images.
- Documentation: original box, warranty card, service receipts, and a serial that matches the caseback.
Parameter Bands Worth Comparing
- Case diameter: this collection runs small, generally in the low to mid 30s in millimeters, with a few larger variants. Measure your wrist before assuming a size works.
- Thickness: moon phase modules add height. Anything unusually thin for the complication deserves a closer inspection.
- Power reserve: automatic Swiss calibres in this class commonly deliver roughly 40 to 70 hours. Ask for the figure and test it.
- Water resistance: dress watches of this type are usually rated for splash resistance only, often around 30 to 50 meters. Do not treat that as swim rating.
- Service interval: budget for a full service every five to seven years on a mechanical moon phase.
Common Pitfalls
- Swiss made claims with no supporting documentation. The designation is legally protected and tied to specific manufacturing criteria, so it is not a marketing phrase a seller can assign freely.
- Stock photography reused across multiple listings. Ask for a timestamped photo of the caseback and movement.
- Replica listings that promise identical construction. Parts are not interchangeable with the original, independent watchmakers often decline the work, and there is no manufacturer service channel.
- Import risk. Counterfeit watches are subject to seizure at the border, and the buyer can face civil penalties on top of losing the money.
- No return window. A seller who will not accept a return after authentication is telling you something.
FAQ
Is a replica Rendez-Vous Moon Phase the same watch at a lower price?
No. It is a different object with a different movement, different materials, and no manufacturer support. Resale value and serviceability are not comparable.
What does reference 240 mean on this model?
It depends on the seller. It may point to a calibre, a case configuration, or an internal inventory code. Get the meaning in writing before you compare prices.
Which documents matter most?
A warranty card or service record with a matching serial, plus original packaging. Receipts from an authorized service center carry more weight than a seller's own description.
Can an independent watchmaker service a moon phase complication?
Many can, but they need parts. For an authentic watch, parts availability through the brand network is the reason documentation and provenance matter so much.