|Winding:||Automatic, Bi-Directional Automatic Winding|
|Diameter:||26.50 mm (11.5 ligne)|
|Complications:||Date, Hacking Seconds, Hand Winding, Quick Date Correction|
|Hands:||Central Hour Hand, Central Minute Hand, Central Seconds Hand, Date Window at 3:00|
|Distinguishing Technical Characteristics|
Counter-Clockwise Balance Cock
|Production: 2007 – 2013|
Cal. 4L75 is a high-end slim automatic movement with date from Seiko. Produced from 2007 through 2013, it was part of the Seiko 4L/6L family, which was similar in design to the Soprod A10 family of Swiss movements. It is exactly the same size as the popular ETA 2892A2, and has similar specifications as well, though the design is completely different.
Cal. 4L75 differs from the preceding Cal. 4L25 in details of finishing and regulation. Both have the same specifications, features, and dimensions.
Cal. 4L75 was used in two Seiko Credor models in the Signo and Node family:
- 2007-2012 Credor Signo GCBW999
- 2007-2011 Credor Signo GCBW997
- 2008-2011 Credor Signo GCBW995
- 2008-2011 Credor Signo GCBW993
- 2008-2012 Credor Node GCBW991
- 2008-2013 Credor Node GCBW989
Seiko 4L/6L Family History
The Seiko 4L/6L movement family is extremely rare, having only appeared in three versions in upscale and rarely-seen watches. The first member of the family, Cal. 4L25, was listed in the Seiko catalog from 2006 through late 2008 in the SARA watch line. Cal. 4L75, an upscale version, appeared in 2007 in the Credor Signo and Node lines and was retired in 2013. These differed only in accuracy (-15/+25 vs. -10/+15) and finishing. The movement returned in 2018 as Cal. 6L35, briefly used in a limited-edition Presage model, before returning to full production for Credor’s GCCD line in 2019 as Cal. 6L75.
There is no question that Seiko was working on this movement much earlier, however. It was talked about in the early 2000s, and Soprod began using the design as the basis for their Alternance 10 family in 2004. The movement continues to be produced by Soprod as Cal. M100, making it likely that far more Swiss offspring have appeared than Seiko-branded models.