Seiko 9S5x Family

BRANDS: Credor, Grand Seiko, Seiko, Shizukuishi Watch Studio

Production: 1998 – Current
1910s	1920s	1930s	1940s	1950s	1960s	1970s	1980s	1990s	2000s	2010s	2020s

Seiko introduced the flagship 9S family of movements in 1998 for their growing Grand Seiko line. Similar movements under the 8L name were later used in the Brightz, Credor, Galante, and Prospex lines. It was a modern 28,800 A/h movement with Seiko’s signature Magic Lever bi-directional winding system.

	Production	Application	Winding	Jewels	Notes
8L21	2003-2007	Brightz SAGL	Automatic	24	Similar to 9S51
8L34	2000	Railway pocket watch	Manual	20	Small seconds
8L35	2000-present	Brightz SAGQ Prospex SBDX Prospex SLA	Automatic	26	Date, similar to 9S55
8L36	2011-present	Credor GCBZ Galante SBLM	Automatic	27	GMT, similar to 9S56
8L38	2010-2015	Galante SBLL	Automatic	26	Open Heart
8L75	-2005	Credor GCBR	Automatic	26	Date, similar to 9S55
9S51	1998-2009	GS SBGR	Automatic	24	No date
9S54	2001-2010	GS SBGW	Manual	20	No date
9S55	1998-2010	GS SBGR	Automatic	26	Date
9S56	2002-2010	GS SBGM	Automatic	27	GMT, no date

Calibre	Start Year	End Year	Complications
Seiko 8L21	2003	2007	Hand Winding
Seiko 8L34	2000	2000
Seiko 8L35	2000	Current	Date, Hand Winding, Quick Date Correction
Seiko 8L36	2011	Current	24 Hour Hand, GMT Hand, Hand Winding, Independently-Adjustable 12 Hour Hand
Seiko 8L38	2010	2015	Hand Winding
Seiko 8L75		2005	Date, Hand Winding, Quick Date Correction
Seiko 9S55	1998	2010	Date, Hacking Seconds, Hand Winding, Quick Date Correction