Short answer

A replica Lange 2 Perpetual is a counterfeit take on A. Lange & Söhne's Lange 1 Perpetual Calendar line. The genuine watch carries an in-house L021.3 movement with a true perpetual calendar that accounts for month lengths and leap years, plus a moon-phase display that drifts one day in roughly 122 years. Replicas in the $400 to $1,200 range do not. Nearly all of them stack a calendar and moon-phase module on top of a stock automatic movement, so the result is a watch that looks complicated and behaves like a simple date. Treat the purchase as costume jewelry with a movement inside, not as a calendar instrument.

Prerequisites

  • A reference photo of the genuine model for side-by-side comparison, ideally the 41.9 mm Lange 1 Perpetual Calendar.
  • A budget you are willing to lose. Replica calendar modules have no parts supply and no factory service.
  • A seller who will send a live movement photo or video before you pay.

Movement types you will meet

  • Modified Seagull or Miyota automatic with a bolted-on calendar plate. This is the most common setup. Day, date, and month advance on a plain 31-day cycle.
  • Hand-wound chronograph base with a decorative calendar module. It looks busy through a display back, and the calendar still ignores February.
  • Swiss ETA base with an aftermarket module. Rare and expensive, and the module is usually the failure point.

How to check one step by step

  1. Ask for the reference number and confirm the case size you want; the genuine piece measures about 41.9 mm across and 12.1 mm thick.
  2. Request a clear photo of the movement with the case back removed. A blurry shot or a stock image is a stop sign.
  3. Set the watch to the first of the month and advance the date. A true perpetual calendar jumps from February 28 to March 1 in a non-leap year; a replica rolls to February 29 or 30.
  4. Push the corrector at 4 or 8 o'clock and watch whether the day and month discs move together or stagger.
  5. Leave the watch flat overnight and check the moon phase. If the disc completes a full cycle in 24 hours, it is a day and night indicator, not a moon phase.
  6. Inspect the outsize date window under a loupe. Both digits should sit on the same plane with even gaps and matching fonts.
  7. Run a fingernail along the lug edges and case flanks. Better replicas have beveled lugs; cheap ones have rounded, polished blobs.
  8. Weigh the watch in hand. A stacked module adds height, so most replicas land between 12.5 mm and 13.5 mm and feel top heavy.
  9. Test the crown in every position and confirm that winding and time setting feel smooth rather than gritty.
  10. Pay through a method that allows a dispute, then photograph the watch within the return window.

Red flags

  • "Swiss 1:1" claims paired with photos lifted from a forum thread.
  • A working moon phase promised at a price under $300.
  • No movement photo, no video, and no stated return policy.
  • A date that snaps over at midnight instead of rolling across a two-hour window.

What you are actually buying

In the better tiers you get a solid case, a sapphire crystal, and a cleanly applied dial. You get nothing from the calendar. Budget for one service that no watchmaker will perform on a no-name module, and never plan to move it as anything other than what it is.