1940/50 Jaeger-LeCoultre Atmos perpetual motion clock. Calibre 519/Serial number 51620 Production year: Between 1940 and 1950 Movement: Perpetual motion Mechanism: Jaeger-LeCoultre Dial: light grey with gold arrow hour markers and Arabic numerals Dial diameter: 12 cm. Metal: Brass Casing diameter: Height: 23.5 cm. Width: 21 cm. Depth: 16 cm. Weight: 4.200 kg This clock works with the changing of the temperature. A coil set inside the cylinder situated on the back of the clock expands or compresses with the rise or fall in temperature, which allows the clock to work. In working order and keeps good time. All of the glass is intact. It has some signs of wear and tear on the brass of the external casing. The mechanical part is perfect. Light grey dial. The numbers 3, 6, 9, and 12 are Roman numerals, with a distinctive trait that the numbers 3 and 9 are inverted. In order for the clock to function properly it must be set on a level surface. The clock must not be moved without adjusting the locking lever of the balance wheel from the left to the right. It is rare to find an old clock with such a low serial number that still works well. Insured shipping with tracking.