This is the first model of the Reverso – Jaeger-LeCoultre’s most iconic timepiece – to be equipped with an automatic movement. The Caliber 967/B has a 42-hour power reserve, and drives a 24-hour second time zone subdial that replaces the numeral 6 on the dial. The day/night indication is unique and ultra-subtle. It differentiates daytime hours from nighttime hours with contrasting guilloché finishes on the subdial at 6 o’clock: day hours are indicated in a swirled pattern above the 6 to 18 half of the dial, while a horizontal pattern on the lower half indicates the night hours. The main dial is guilloched in a Clous de Paris pattern. The Reverso, with its reversible case, was developed in the 1930s at the request of British army officers stationed in India, who wanted to protect their watch dials while playing polo. Aside from 18k rose gold, there is a stainless steel version of this watch. The caseback of either can be engraved with a monogram.