Answer first
"Fake Zeitwerk 306.104" is a search string, not a watch model. A. Lange & Söhne makes the Zeitwerk. Catalog references for that line begin with 140, 142, 145, or 148. No manufacturer lists a Zeitwerk under 306.104. That number comes from a marketplace listing, a factory batch tag, or a dealer's internal SKU. When a listing joins the word Zeitwerk with 306.104, the pairing is unverified.
What the number 306.104 points to
Reference numbers in the watch trade follow house rules. Lange uses a three-digit family code plus a three-digit variant code. The 306 family does not belong to the Zeitwerk line. Sellers of first copy watches often invent codes that look close to real ones. A buyer sees six digits and assumes a catalog entry exists.
- 140 to 149: Zeitwerk families in published Lange material.
- 306: not a Zeitwerk family code in any Lange catalog we can find.
- 104: variant suffix. Suffixes alone carry no meaning.
How to read a listing that uses this code
- Ask the seller for the caseback engraving, photographed in daylight. Real references are cut into the metal, not printed.
- Compare the stated case size with the maker's published size for that line. Zeitwerk cases run about 41.9 mm.
- Check the price. A working Zeitwerk sells in the tens of thousands of dollars. A first copy at two or three hundred dollars is a copy.
- Request a movement photo. The Zeitwerk uses a jumping-hour, minute-repeating caliber. Copies use generic quartz or automatic movements.
- Search the exact six digits alone, without the brand name. Dealer sites will show what the code actually belongs to.
Legal status in the United States
US Customs and Border Protection seizes counterfeit watches at import. Buying, shipping, or reselling a counterfeit mark violates the Lanham Act. Penalties apply to the seller and to the importer. Civil damages can reach the retail value of the genuine item.
What we do not know
We found no manufacturer document, auction record, or service paper linking 306.104 to any Zeitwerk. If a seller shows such a document, verify it with the maker directly before paying.