Quick answer

A fake Villeret Ultra Thin is a replica of the Blancpain Villeret Ultraplate. The genuine reference 6605 measures 40 mm across and 7.39 mm thick. Calibre 11A4B runs at 28,800 vph (4 Hz) with a 100-hour power reserve and a silicon balance spring. Most replicas copy the dial layout. They miss the case depth. A stock automatic movement needs 9 mm to 11 mm of case height. That gap is the first thing to measure.

Genuine specification

  • Case: 40 mm, 18k red gold or 18k white gold. Blancpain does not list a stainless steel Ultraplate.
  • Thickness: 7.39 mm.
  • Movement: calibre 11A4B, automatic, 4 Hz, silicon balance spring.
  • Power reserve: 100 hours.
  • Crystal: sapphire front and back.
  • Dial: applied gold indices, small seconds at 6 o'clock, printed "Blancpain" and "Automatique".

Blancpain revises references and dial variants. Confirm the numbers on the current spec sheet for the exact reference you compare.

Where replicas diverge

1. Case thickness and weight

Use a caliper. A replica reads 9.5 mm to 11 mm. Gold is dense. A solid 18k case at 40 mm has heft that a plated brass case does not. A kitchen scale shows the difference in grams.

2. Movement finish

Genuine calibre 11A4B shows Cotes de Geneve stripes on the bridges, perlage on the base plate, and a signed rotor. Copies use a stock 3 Hz or 4 Hz automatic with 38 to 42 hours of reserve. Look at the balance wheel and the jewel count through the display back.

3. Dial and hands

Genuine indices are solid gold with polished facets. Replicas glue printed or plated markers. Under a 10x loupe, genuine pad printing holds sharp edges. Replica ink bleeds at the serifs. The small seconds hand is thin steel, not painted.

4. Caseback markings

Reference and serial numbers sit between the lugs on a genuine case. A pantograph cuts them to a set depth. Laser marks on replicas look shallow and sit off-center. Caseback engraving should match the reference on the warranty card.

Price and legal status

Genuine Villeret Ultraplate watches sell in the five-figure USD range. Counterfeit watches are illegal to import into the United States. U.S. Customs and Border Protection seizes them under 19 U.S.C. 1526. Selling a counterfeit watch creates trademark liability for the seller. Independent repair shops decline replica work, and replacement parts come from the same factories that built the watch.