Quick answer
The A. Lange & Söhne 1815 Rattrapante Perpetual Calendar is a hand-wound split-seconds chronograph with a perpetual calendar. Lange launched it in 2013 in platinum, 41.9 mm wide, in a run of 100 pieces. Replicas of this reference are rare. No factory has published a working split-seconds caliber for it. Most listings that carry the name sell a standard chronograph with a second hand that does not split.
Specs of the genuine watch
- Reference: 421.025, platinum
- Case: 41.9 mm, platinum
- Movement: L101.1, hand-wound, 631 parts, 43 jewels
- Functions: split-seconds chronograph, perpetual calendar, moon phase
- Production: 100 pieces, 2013
- Retail at launch: reported above US$150,000
Why the replica supply is thin
A rattrapante needs a second column wheel, a clamp, and an isolator. That is more parts and more assembly time than a plain chronograph. Factories that build Rolex and Audemars Piguet replicas work from high-volume tooling. Lange production is reported at about 5,000 watches a year across all models. One reference cannot carry that tooling cost, so few makers attempt it.
What replica listings show
Photos in these listings show a case with two pushers, one at 2 o'clock and one at 4 o'clock, plus a crown. The split hand is often fixed to the chronograph runner. It starts and stops with the main chrono hand. It does not stop on its own while the other hand keeps running. Ask for a video with a running timer in frame. If the seller cannot show a hand that stops and then catches up, the movement is not a rattrapante.
Movements named in listings
- Seagull ST19: hand-wound chronograph, no split function in the base version.
- ST19 variants: some sellers call these split seconds. Check the pusher layout and the video.
- ETA 7753 and Sellita SW510: chronograph, no split function.
Split-seconds movements cost more to build in every market. A working one at US$400 is not a split-seconds caliber.
Case and dial tells
Platinum has a density near 21.4 g/cm3. Steel sits near 7.9 g/cm3. A platinum case weighs more than a steel case of the same size, and sellers do not publish weight in most listings. The genuine dial is solid silver with blued steel hands. Replica dials are brass or steel with plating. Caseback engraving on a replica is shallow, and photos show lettering that differs from the Lange script.
Legal status in the United States
Counterfeit watches are illegal to import and sell in the US. 18 U.S.C. § 2320 covers trafficking in counterfeit goods, with fines and prison terms. US Customs and Border Protection seizes counterfeit watches at ports and destroys them. A buyer who pays an overseas seller after a seizure has little chance to recover the payment.
Price comparison
- Genuine 421.025: auction results reported from about US$120,000 to US$200,000.
- Listings that use the name 1815 rattrapante: US$300 to US$900.
- The price gap matches a plain chronograph movement, not a split-seconds caliber.
Checks before payment
- Video of the split function with a timer in frame.
- Photos of the movement, not stock images.
- Caseback and reference number photos.
- Return policy in writing.