The famed Jaeger-LeCoultre "Memovox" (voice of memory) was introduced to the market in 1950, quickly gaining traction in the market as one of the most desirable and reliable alarm watches. A center disc with an arrow is operated by a second crown at two o'clock. In an era where sports diving was gaining more and more popularity (indeed, advertisements of the era branded the E859 as "pour l'homme d'action" or "for the man of action"), Jaeger-LeCoultre's response was to meet that demand and create an oversized, automatic waterproof divers' wristwatch - with an alarm function.

Jaeger-LeCoultre's goal was to offer both visual (inner bezel) and auditory (alarm) timers for the dive. To do so, the firm created a patented caseback, which optimized the alarm's sound transmission underwater. The outer case, with its 16 holes, allowed for the alarm tone to be heard and felt on the wrist, while the inner case sealed and protected the movement. The watch featured three crowns, each with the cross hatch pattern characteristic of Super Compressor watches: the first for time setting, the second for the inner bezel for dive timing, and the third to rotate the inner disc with arrow to set the alarm.

Known in the United States as the Polaris, and in the European market as the 'Skin Diver Memovox', the reference E859 was made in 1714 total examples between 1965 and 1969, and finding these precious timepieces in their original and unmolested condition has become increasingly difficult. The present model was made for the European market, as indicated with the full Jaeger-LeCoultre brand name on the dial, whereas the simplified "LeCoultre" brand was used on dials of models intended for the American market.