Short answer

33702 is not a Cartier model reference. It's a case number stamped on the back of the Ballon Bleu de Cartier, and it shows up in search results because replica sellers copy it into listing titles. If you searched for a fake Ballon Bleu 33702, you're looking at a watch being sold as genuine with that number in the description, or at a replica listing that borrowed the number to look official. Either way, the number by itself proves nothing. What matters is the W-prefix reference, the serial, and the watch in your hand.

What the number on the caseback means

Modern Cartier watches carry two identifiers. The reference, which starts with W, tells you the model, size, metal, and strap. The case number is a separate stamp that identifies the case shape and generation, and it gets reused across thousands of watches. A steel Ballon Bleu and a two-tone version can share case numbers across production runs. That's why one photo of a caseback can float around the internet for a decade and turn up in dozens of listings.

Replica sellers figured this out early. A title that reads "Ballon Bleu 33702" sounds specific and technical. It matches what a buyer sees on the back of the watch. It also sidesteps the reference number, which is the part an experienced buyer will actually check against Cartier's own listings.

How to tell a replica Ballon Bleu from the real thing

The crown and cabochon

The blue synthetic spinel set into the crown is a Cartier signature. On genuine watches it sits flush, has a deep even blue, and follows the curve of the crown guard. Replicas tend to use plastic or glass that looks flat and bright, often off-center or glued in with visible residue.

Dial and printing

Ballon Bleu dials use a guilloché pattern of concentric rings. Fakes usually stamp or print it, so the texture looks shallow and the rings blur near the center. Look at the Roman numerals. On real dials the VII is printed with clean serifs and consistent spacing. Replicas swap fonts, crowd the numerals, or print them too heavy.

Hands and glass

Genuine hands are heat-blued steel, which gives a matte, slightly uneven blue. Painted hands look glossy and uniform, and they chip at the tip. The crystal should be sapphire with almost no reflection at an angle. Mineral glass on fakes scratches fast and shows a slight halo around the edges.

Caseback engraving

Cartier engraves deep, sharp letters and numbers with consistent depth. Replicas laser-etch shallow text that catches the light differently at each angle. Check the alignment of the case number against the reference. Check for a serial number. A missing or mismatched serial is the fastest red flag.

Movement and weight

Some Ballon Bleu models show the movement through a caseback. Genuine Cartier calibers are finished with Geneva stripes and rotors that look machined, not stamped. Cheap fakes drop in an unbranded Chinese automatic and etch "Cartier" on the rotor. Steel replicas also feel light in a way that's hard to describe until you hold a real one. Gold-plated fakes flake at the lugs within months.

What you risk by buying one

The legal side is not a gray area. Counterfeit goods are seizable at the US border even in single-item shipments, and Customs can destroy them with no compensation. Selling one later is trademark infringement, plain and simple.

The practical side is worse. Cartier service centers will not touch a counterfeit. Independent watchmakers refuse too, since parts availability and liability both become problems. There's no warranty, no service history, and resale value near zero. A replica that costs $300 and dies in two years cost you $300. A genuine Ballon Bleu bought used at a fair price holds most of its value.

If you want the real watch, buy it this way

  • Buy the seller first. A long history of watch sales with feedback beats any single listing.
  • Ask for photos of the caseback, the serial, and the movement before you pay.
  • Take the watch to a watchmaker for authentication if the seller won't meet you at one.
  • Compare the asking price against recent sold listings. A steel Ballon Bleu for $900 is a fake, no exceptions.
  • Prefer sellers who include the box, papers, and a service record with matching numbers.

Quick checklist

  • Reference starts with W and matches the model and size.
  • Case number and serial both present, aligned, and deeply engraved.
  • Crown cabochon flush, deep blue, correctly shaped.
  • Dial texture is cut, not printed.
  • Hands are blued steel, not paint.
  • Price reflects the real market, not a bargain that feels too good.

None of this makes for a glamorous answer. The honest one is that 33702 is a case number, replicas borrow it, and the only reliable test is the watch in front of a trained eye. Do that before you hand over money.