Short answer
A Villeret 8 Days reproduction is a copy of the Blancpain Villeret 8 Jours, reference 6630. The genuine watch runs a hand-wound caliber 13R0 with a 192-hour power reserve. No replica on the market matches that number. Most copies run a 40-hour automatic movement and a power reserve arc that does not move.
What 8 days means on the real watch
Blancpain fits three mainspring barrels in series inside caliber 13R0. A full wind gives 192 hours, or 8 days, before the watch stops. The barrels sit in a stack, so the case stays near 12 mm thick. A power reserve scale on the dial shows the hours left.
Movements used in reproductions
- Automatic 21,600 vph (3 Hz) unit on an ETA or Seagull base. Reserve is 36 to 42 hours.
- Hand-wound copies with two barrels. Reserve measures 70 to 100 hours on a test bench. This is the closest option.
- Quartz units. No reserve. The power reserve hand is fixed.
Ask the seller for a movement photo and the caliber name. A listing that says 8-day reserve with no caliber number is a guess.
Case, dial and size
Genuine Villeret 8 Jours cases come in 38 mm and 42 mm, in steel, rose gold and white gold. Replicas sit at 41 to 42 mm and 12.5 to 13.5 mm thick. Dial options include grand feu enamel, opaline and a sunray finish. Check three points. The Roman numerals should be printed, not decals. The small seconds hand should sweep at 3 Hz or 4 Hz, not tick once per second. The date window, when present, should sit at 3 o'clock and align with the dial curve.
Price bands
Low grade copies sell for 80 to 150 USD. Mid grade runs 200 to 350 USD. High grade runs 400 to 700 USD. Above 700 USD you pay for a name, not parts.
Checks before you buy
- Caseback photo. Look for an engraved movement ring, not a printed plate.
- Timegrapher reading. Rate inside plus or minus 15 seconds per day.
- Water resistance claim. Most copies hold 30 m at best. Do not swim.
- Strap. Genuine uses alligator. Copies ship with calf or synthetic leather.
Legal note
Blancpain and Villeret are registered trademarks of the Swatch Group. Sale of copies is illegal in the United States and the European Union. Customs seizures occur. I have no data on seizure rates for this model.