What the ref 5402 is

Audemars Piguet launched the Royal Oak ref 5402 in 1972. Gérald Genta drew the case. The steel case measures 39 mm across and about 7 mm thick. Eight hexagonal screws sit on an octagonal bezel. The bracelet is integrated into the case. The dial uses a raised grid pattern AP calls Tapisserie.

The ref 5402 ran from 1972 to about 1977. Later Jumbo references followed: 14802, then 15202 in 2000, then 16202 in 2022. The 5402 is the first. Collectors call it the Jumbo because the case is thin.

Movement in the genuine ref 5402

Inside is Caliber 2121. It is an automatic movement that comes from the Jaeger-LeCoultre Caliber 920. Patek Philippe and Vacheron Constantin used the same base. The movement is about 3 mm thick, which is why the case sits flat on the wrist. A date window sits at 3 o'clock.

What replica makers copy

A replica ref 5402 copies four things: case profile, bezel screws, dial texture, bracelet links. Check these points.

  • Case diameter. Genuine is 39 mm. Many replicas use 41 mm or 42 mm.
  • Case thickness. Genuine is near 7 mm. Replicas with a stock automatic movement run 10 mm and up.
  • Screw slots. Genuine screws are functional and align on one axis. Many fakes use glued caps. Check that all eight slots point the same way.
  • Dial. Tapisserie squares should be raised and even. A printed grid looks flat under light.
  • Bracelet taper. Links narrow from the case to the clasp. A straight bracelet with no taper is a low grade build.
  • Date font. Genuine date wheels use a thin font. Bold fonts point to a cheaper replica.

Movements used in replicas

Common choices are the Miyota 9015, the Seiko NH35, and Chinese movements that copy the 2121 layout. The Miyota 9015 is 3.9 mm thick. The NH35 is thicker. Case thickness follows the movement inside.

Prices and grading

Replica prices for a ref 5402 run from about $80 to $500. Price tracks case finishing, dial texture, and movement. Steel is the common material. Two-tone and gold plated versions exist.

How to check a listing

Ask for measured case diameter and thickness with calipers. Ask for the movement model. Ask for photos of the caseback, the clasp, and the crown. A genuine 5402 caseback carries a reference number and a serial number. Replica casebacks copy the text but not the serial history.