Short answer
"Fake Type XX 3820" is a search phrase for a copy of the Breguet Type XX Transatlantique, reference 3820. Breguet is a Swiss maker founded in 1775. Reference 3820 is a steel automatic chronograph with a date and a 24-hour display. Listings for copies use terms such as "1:1", "first copy", or "Swiss movement".
No replica sold at copy prices matches a genuine watch part for part. The "1:1" label is marketing text.
What reference 3820 is
The 3820 belongs to the Type XX Transatlantique line. The better known Type XX Aeronavale carries reference 3800. The two share a case family and a chronograph layout, but differ in dial details and displays.
- Case: stainless steel, round, about 39 mm to 40 mm depending on the catalog.
- Function: hours, minutes, small seconds, chronograph, date, 24-hour indicator.
- Movement: Breguet-signed automatic chronograph caliber built on a Lemania base.
- Crystal: sapphire with anti-reflective coating.
- Status: discontinued. Used examples trade at auction and on the pre-owned market in the four-figure USD range.
Movements found in replica 3820s
- Asia 7750. Automatic, 28,800 vph, subdials at 12, 6, and 9. Common and cheap. Rotor noise is audible.
- Seagull ST19. Hand wound, column wheel. Used in builds that need a thin case or an open back.
- Quartz. Subdials are decorative or run on separate motors. The chronograph hand jumps once per second.
The subdial layout is the fastest tell. A genuine 3820 uses its third register for a 24-hour display that moves at half the rate of the hour hand. A 7750 build cannot copy that without a module, and most sellers do not fit one.
Checks buyers run before paying
- Measure the case with calipers. Replica cases often run 0.5 mm to 1 mm wider than the published figure.
- Watch the 24-hour indicator for a full day. It should complete one turn in 24 hours, not 12.
- Turn the crown and pushers. Screw threads should seat with light pressure and no grit.
- Check dial printing under a loupe. Signature spacing, font weight, and the position of "Swiss Made" are the weak points.
- Read the caseback engraving. Reference and serial numbers should be cut, not printed.
- Test water resistance, or accept that it is unknown. Most copies ship without a pressure test.
Prices
Copies of the 3820 sell from about $150 to $600. Price tracks the movement and the case finishing. Genuine Type XX Transatlantique watches sell used for several thousand USD. A listing that asks four figures for a copy is priced wrong.
Legal and service notes
US customs can seize counterfeit watches at import under 19 U.S.C. 1526. Breguet service centers do not accept copies, and no parts account exists for the brand. Asia 7750 parts are sold by watch supply houses, so a local watchmaker can service that movement. The number 3820 is a case reference. Movement numbers in this family follow a different sequence.