ST1812

	Brand:	Sea-Gull, Tianjin
	Family:	Unknown
	Height:
	Jewels:	21, 23
	Reserve:	41 hours
	Frequency:	28800 A/h
	Winding:	Automatic, Bi-Directional Automatic Winding, Central Rotor Automatic Winding
	Diameter:
	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
Central-Rotor Automatic Clockwise Balance Cock Screw Regulator
Production: 2001 – Current
1910s	1920s	1930s	1940s	1950s	1960s	1970s	1980s	1990s	2000s	2010s	2020s

Cal. ST1812, produced by Tianjin Seagull Corporation, is an automatic movement with a central date wheel. The design is similar to the ETA 2892A2.

Besides finishing, there are some differences between Cal. ST1812 and ETA’s Cal. 2892A2. Cal. ST1812 uses a traditional fixed pin balance instead of the ETACHRON balance in the 2892 and has a fully slotted excentric in the regulator. The balance bridge is mounted using holes instead of pins as on the ETA. The fourth wheel on Cal. ST1812 also have six instead of eight spokes and places the winding jewel on the post bearing instead of the bridge. Some examples have an extra jewel for the barrel arbor.