Short answer
A fake Reverso Tribute Duoface is a Chinese-made copy of Jaeger-LeCoultre's two-dial Reverso, and the good ones are judged on four things: the case measurements, the flip mechanism in the cradle, the finishing on both dials, and whether the second time zone actually sets the way a Duoface should. Get those four right and the watch reads correctly on the wrist. Miss the thickness or the track tolerances and no amount of dial work saves it.
What the Duoface actually does
The Duoface is one movement driving two dials, one on each face of a case that slides and flips inside its cradle. The front shows local time; the back carries a second time zone plus a day/night indicator. On the genuine watch the movement is a manual-wind caliber from the 854 family, the steel Tribute case measures about 47.0 by 28.3 mm at roughly 10.3 mm thick, and the second zone is adjusted independently of the main time. Any replica that cannot do those things is a Reverso-shaped object, not a Duoface.
Prerequisites
- A digital caliper that reads to 0.1 mm
- A 10x loupe
- A bright, raking light source (a desk lamp angled across the dial)
- The published specs for the exact reference you are comparing against, on screen next to you
How to inspect one
- Measure length, width and thickness with the caliper and write the numbers down. Compare against 47.0 x 28.3 mm and about 10.3 mm; a replica over 11 mm thick has a stacked or oversized movement and will sit wrong.
- Flip the case through the cradle at least a dozen times. It should travel with steady resistance and click into both positions with a firm detent, with no side-to-side play in the track.
- Look at the cradle rails and screws under the loupe for burrs, uneven polishing and off-center slots.
- Tilt the front dial under the raking light and watch the sunray brushing. It should shift tone in one clean sweep, not in patches or with visible machining lines.
- Inspect every applied index at magnification: seated flat, sharp inner corners, polished facets that catch light in a single line.
- Check the dauphine hands for a crisp center crease and no rounded, soft edges where the two facets meet.
- Turn the watch over and look at the second dial. The day/night disc must sit centered in its aperture, and the printing on the second time zone ring must be sharp and evenly spaced.
- Set the watch through a full cycle: pull the crown, set the front time, then move the second zone and confirm it jumps in clean one-hour steps without dragging the main time.
- Wind it 30 turns and listen. A dry, grinding or rattling sound means the movement is unfinished or the stem is misaligned.
- Inspect the strap, spring bars and any deployant, then assume nothing about water resistance.
The usual tells
- Thickness running 1 to 2 mm over spec, which throws off the case profile and the flip geometry
- A second time zone that only mirrors the front dial instead of moving independently
- Engraved reference and serial numbers in the wrong typeface or depth
- Shallow crown logo, soft crown knurling, and a crown that sits proud of the case band
- Printed rather than applied indices on the back dial of references that should have applied markers
- Caseback screws that are decorative rather than functional
Setting and living with it
Wind a manual Duoface replica at the same time each morning and keep it away from water, however good the gaskets look; the seals on copies are not tested to any standard. When you set the second zone, always move it forward through the hours rather than backward, and reset the day/night disc by advancing a full 24 hours. Store it dial-up in a dry place and have it cleaned if the winding starts to feel gritty.
What it should cost
Replica Reversos sit in tiered price bands, and the band usually tracks the movement and the case machining rather than the dial. Expect a few hundred dollars for anything with a functioning independent second zone and a squared-away flip track; cheap examples under about $150 are cosmetic only. Buy from a seller who will show you caliper photos and a video of the flip before you pay, and treat any listing that hides the thickness as a pass.