Quick answer
The phrase replica speedmaster 1957 6th generation comes from sellers. Omega has no generation list for Speedmaster replicas. The number marks a batch inside one seller's own count. A 6th generation copy and a 3rd generation copy can leave the same workshop with different parts.
The genuine reference
Copies target the CK2915, the first Speedmaster. Omega released it in 1957. Case size was about 38 mm. The dial used broad arrow hands. The bezel was steel with an engraved tachymeter scale. Early examples used the base 1000 scale. The movement was calibre 321, a column wheel chronograph.
Omega reissued the design in 2017 as part of the Speedmaster 1957 Trilogy. That version used a 38.6 mm case and calibre 1861. Omega listed the single-piece Speedmaster 1957 at 3,557 pieces.
What 6th generation means
No factory publishes a generation list. Sellers number batches by their own count. The label has no standard behind it. There is no public record to verify a count of six.
Where copies differ
- Case diameter. Copies measure 39.7 mm to 40 mm. The 1957 Trilogy case measures 38.6 mm.
- Subdial spacing. The ST19 movement sets the subdials further apart than calibre 321 or 1861.
- Bezel. Copies often use an aluminum insert with a printed scale. The original used steel with an engraved scale.
- Lume. Some batches use pre-aged yellow paint. Others use white.
- Caseback. Copies carry engraved text and a seahorse. Font weight and depth change between batches.
Movement
Most hand-wound copies use the Seagull ST19. It is a column wheel chronograph derived from the Venus 175. Rate is 21,600 vibrations per hour. Power reserve is about 40 hours. Some lower-cost copies use quartz. Genuine calibre 321 and 1861 parts do not fit the ST19.
Checks before buying
- Measure the case with calipers. Ask for the number in millimeters.
- Confirm the pushers sit at 2 and 4 o'clock.
- Confirm running seconds sit at 9 o'clock.
- Ask for a video of the chronograph start, stop, and reset.
- Ask for a photo of the movement through the caseback.
Legal note
US customs law prohibits import of goods carrying a counterfeit mark. 15 USC 1124 covers seizure and forfeiture. Orders shipped from outside the US carry that risk.