For sale is a very good condition 34mm stainless steel Jaeger-LeCoultre (JLC) Master Ultra Thin. The 145.8.79 was originally retailed in August 1998 and is accompanied by its original box and papers, though the box is missing its pillow.

The JLC features a polished finish steel case with a fixed smooth bezel measuring just 5.4mm thick including the crystal, making it one of the thinnest watches of the 1990s. The Ultra Thin is mounted on a new OEM black alligator strap, secured by a new polished steel OEM tang buckle. The JLC features silver a sunburst dial with applied elongated index and Arabic numeral hour markers, complemented by dauphine hands. The movement used in the 145.8.79 is the manual wind JLC Caliber 849, which features approximately 35 hours of power reserve. 

Significance: 
The JLC Master Ultra Thin reference 145.8.79 set a new standard for dress watches upon its release in the early 1990s. Its steel case measures just 5.4mm thick, making it one of the slimmest watches of the 90s. Collectors often refer to it as “the only one that actually worked properly,” since other ultra-thin watches of the era would stop running if worn too tightly on the wrist. This feat of engineering was made possible by the manual-wind Jaeger-LeCoultre Caliber 849, itself an astonishing 1.49mm thick. Given the complexity of producing such a movement and case, it is rumored that the 145.8.79 was assembled and finished within JLC’s complications department. Well ahead of its time, the reference pushed the boundaries of ultra-thin watchmaking decades before brands began dedicating vast R&D resources to competing for the title of the world’s thinnest watch.

Condition: 
The case retains thick even lugs, crisp edges and engravings, and its original signed crown, though surface scratches are present across much of the polished finish from prior wear. The OEM strap and tang buckle are both brand new, having been recently purchased from JLC, and show no signs of use. The crystal remains free of scratches or blemishes, while the movement is running well and keeping accurate time, though its last service date is unknown.

 - All serial numbers are fully visible but have been covered in the listing photos 

- Feel free to reach out with any questions

Dimensions: 34mm

Box, Papers, etc.: Box & Papers

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