Short answer
"Rendez-vous moonphase 2208420" is a search string, not a factory reference. Jaeger-LeCoultre labels its watches with a Q prefix, for example Q3578430. The Rendez-Vous is a women's collection that the Le Sentier factory introduced in 2012. No public Jaeger-LeCoultre record for the bare number 2208420 was found for this guide. Replica sellers use such numbers as stock codes. Ask for a photo of the case back before you treat the number as a catalog reference.
The genuine watch behind the name
Rendez-Vous Moon models carry a moon phase display, often in an aperture at 6 o'clock. The complication follows the synodic month of about 29.53 days. The disc advances one step per day. Case sizes in the line run from 34 mm to 36 mm. Dials use guilloche or mother-of-pearl, and high jewelry versions add diamond-set bezels. Genuine retail lands in five figures in US dollars.
What replica Rendez-Vous Moon watches do
- Moon disc: many fakes run a 24-hour day and night disc instead of a 29.5-day cycle. Test it. Note the moon position, wait 48 hours, then check again. A real moon phase moves about 1.6 positions in two days. A day and night disc moves two full positions.
- Movement: quartz, or a stock Asian automatic with a glued-on module. No Geneva stripes, no blued screws.
- Glass: mineral crystal on cheap units, sapphire on better ones.
- Plating: gold tone over brass or steel. Weight drops against a solid gold case.
- Case back: shallow engraving, wrong font, missing Q prefix.
Checks before purchase
- Weight and balance in the hand.
- Engraving depth on the case back and clasp.
- Moon disc speed across 72 hours.
- Crown action and date or pointer setting.
- Lume, if the listing claims it.
Price context
Replica Rendez-Vous Moon listings sit between about USD 200 and USD 900 on common marketplaces. Genuine pieces sell in five figures. US customs can seize counterfeit imports under 19 U.S.C. 1526, and the shipment is destroyed. Payment recovery after a seizure is rare.
Bottom line
Treat 2208420 as a seller code. Judge the watch on the moon phase cycle, the case back, and the movement, not on the number in the listing title.