Short answer

"Fake Cartier Santos 162370" is a search phrase used by people shopping for counterfeit copies of a Cartier Santos watch whose caseback carries the number 162370. That number on its own proves nothing. Cartier does not publish a public table that maps every case reference to a model, and counterfeiters routinely copy a real reference number off a genuine caseback and stamp it onto a fake. A counterfeit is a watch made to imitate Cartier's design while carrying Cartier's trademarks without permission. In the United States that makes it infringing merchandise: Cartier will not service it, no manufacturer warranty applies, and US Customs can seize it at the border. If you want the Santos look on a budget, the durable paths are a pre-owned genuine Cartier, an unbranded square-cased homage, or a square watch from a brand that never used Cartier's name.

What the number 162370 points to

The Cartier Santos line began in 1904, when Louis Cartier built a wristwatch for the Brazilian aviator Alberto Santos-Dumont. Over more than a century the family split into Santos Galbee, Santos 100, and the current Santos de Cartier, and the numbering system changed with each era. Cartier case references are stamped on the caseback alongside a separate serial number. The reference identifies the model and case type; the serial identifies that single watch.

A six-digit number like 162370 shows up in listings as a case reference and is often attached to steel Santos models with a square bezel and integrated bracelet. Because the same digits circulate on genuine and fake casebacks alike, treat 162370 as a starting point for verification, not as proof of anything.

How to judge a Santos that claims that reference

Caseback engraving

  • Genuine Cartier engraving is crisp, shallow, and even, with consistent letter spacing.
  • The reference number and the serial number sit in separate lines and should not be the same digits.
  • Fakes often show fuzzy edges, uneven depth, or a font that drifts between letters.

Dial and printing

  • Roman numerals should be clean cut with sharp corners. Blurred or thick strokes are a warning sign.
  • Some Cartier dials hide the brand name inside a numeral, so check known variants before you assume a dial is wrong.
  • Look at the rail track and the seconds subdial ring under magnification. Copies usually show thicker lines.

Case, crown, and bezel screws

  • The crown should carry a blue cabochon. On copies it is often a flat blue dot or a plastic bead.
  • Santos bezel screws should sit flush and follow the curve of the bezel. Raised or mismatched screws are common on replicas.
  • Run a finger along the case flanks. Genuine finishing transitions are smooth; copies leave a ridge.

Movement and feel

  • A genuine automatic winds with light resistance. Gritty or slack winding points to a cheap movement.
  • Case proportions matter. Copies frequently run thicker than the genuine profile.
  • Only a watchmaker opening the case can confirm the movement, and even then a good copy can be hard to call.

Legal and ownership realities in the US

  • Selling counterfeits violates US trademark law, and buyers can lose the watch to seizure with no refund.
  • Cartier service centers will refuse a counterfeit, so repairs fall to independent watchmakers who may not stock parts.
  • Resale is effectively closed. Auction houses, dealers, and trade platforms reject counterfeit goods.
  • No warranty, no insurance coverage in most cases, and no recourse if the seller disappears.

Legal ways to get the square Santos look

  • Pre-owned genuine: older steel Santos references trade below new retail and hold value. Best for long-term ownership.
  • Unbranded homage: square cases with exposed screws and no Cartier trademarks. Legal, serviceable, and inexpensive.
  • Independent square watches: brands that never used Cartier's name offer similar proportions with real warranties.

Which route fits you

If you want a watch you can insure, service, and pass on, buy pre-owned genuine or save for new. If you want the silhouette and do not care about branding, an unbranded homage gives you the same lines at a fraction of the cost with no legal exposure. If a seller insists a 162370 piece is genuine at a fraction of market price, walk away. The number on the caseback is the easiest thing in the world to copy.