Zenith 672

	Brand:	Zenith
	Family:	Zenith Elite
	Height:	3.75 mm
	Jewels:	27
	Reserve:	55 hours
	Frequency:	28,800 A/h
	Winding:	Automatic, Bi-Directional Automatic Winding, Central Rotor Automatic Winding
	Diameter:	25.60 mm (11.5 ligne)
© Zenith	Complications:	24 Hour Hand, Date, GMT Hand, Independently-Adjustable 24 Hour Hand, Instant Date Change, Quick Date Correction
	Hands:	Central 24 Hour Hand, Central Hour Hand, Central Minute Hand, Central Seconds Hand, Date Window at 3:00

Distinguishing Technical Characteristics
Central-Rotor Automatic Clockwise Balance Cock Balance at 1:30 Barrel at 7:30 Central Rotor
Production: 1996 – 2014
1910s	1920s	1930s	1940s	1950s	1960s	1970s	1980s	1990s	2000s	2010s	2020s

Cal. 672 is a thin automatic movement with date and adjustable 24 hour hand from Zenith. Closely related to other Zenith Elite movements, Cal. 672 is the most complicated early Elite movement yet still measures just 3.75 mm in height. Like the similar Cal. 670, Cal. 672 has central seconds, which is unusual for a Zenith Elite movement. A similar movement with small seconds at 9:00 is Cal. 682.

The central 24 hour hand is adjusted using a pushbutton located at 10:00 on the outside of the case, giving these watches a distinctive look.

Cal. 672 was an early Elite movement, and has been used widely in Zenith watches between 1996 and 2014. Production ended in 2014 when the early Elite movements were set to be replaced by Zenith’s Cal. 3000 (Sellita SW300) and Cal. 6150 series. Although the company has returned to the Elite series as of 2020, the 24 hour movements have not yet been reissued.

Technical Aspects of the Zenith Elite Movement

The basic Elite movement measures 11.5 ligne (25.60 mm) diameter and most models are under 4 mm thick, despite a central automatic winding rotor and date complication. A few models used a larger main plate to move the date window outward or to support complications like a running 24 hour ring. The thinnest Elite movement is the hand-winding Cal. 650 at 2.83 mm and the thickest and most complicated is the large Cal. 687 at 6.20 mm.

Unusually, many Elite movements (apart from the 660 and 670 lines) feature small seconds at 9:00, a distinctive feature that differentiates the watches that use it. Some, however, feature central seconds, an adjustable 24 hour hand, a power reserve indicator, and other complications.

All Elite movements use an annular Glucydur balance wheel with a self-compensating balance spring and fine micrometer screw for adjustment. The automatic winding rotor is mounted on ball bearings like the ETA 2892 and originally included a tungsten carbide element for higher winding power. Most Elite movements boast 50 to 55 hours power reserve and all operate at 28,800 A/h.

Zenith Elite 670: Central Seconds

Cal. 670 was one of the original Elite movements, and remains in production as of 2020. It has central seconds, unlike most Elite movements, and serves as a base for a few complicated versions. Cal. 670 SK, introduced in 2018, is especially notable, as it includes a silicon escapement and is often skeletonized.

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