The saying, “Time is of the essence” takes on a whole new meaning when you’re in the depths of the ocean and pretty much left to your own devices, and defenses. When it comes to the extreme sport of scuba diving, where every second in excess is just as worrying as every second missed, a sturdy, reliable and accurate watch is likely just as important as that oxygen tank strapped to your back. Jaeger-LeCoultre’s Deep Sea Chronograph promises to deliver this much- needed sense of security.

We looked at another notable timepiece for keen divers and Blancpain collectors.

Equipped with an operating indicator, the diver can quickly check if the chronograph is indeed working; that is, if it’s really measuring set time intervals, if it’s ready to be activated, and be assured that the correct time is displayed on the various counters.

For this lifesaving feature, the manufacturer looked to one of its earlier chronographs, the Chronofight of the 1930s, which was designed for civil and military aviation and equipped with sub dials and totaliszers, primarily to make out total flight times while deducting stopovers. Jaeger-LeCoultre The manufacture adapts and tweaks the feature and puts it on the Deep Sea Chronograph, a modern interpretation of the vintage model that was introduced at this year’s SIHH. A round aperture made with red and white discs makes this operating indicator, which is conveniently placed above the logo. When the display is white, the chronograph is ready to be activated. The indicator window displays both colours to signal that a measurement is in progress, and when the chronograph is stopped, the red disc appears to indicate that the measurement is completed.

The powerful piece is equipped with the new automatic Jaeger-LeCoultre Calibre 758, which has up to 65 hours of power reserve. The chronograph has hour and minute counters, as well as a central sweep second hand; hour markers, scales and hands are all luminescent. All these are housed in a 42mm stainless steel case, fitted with a black leather strap.

Jaeger-Lecoultre Deep Sea Chronograph

Movement: Jaeger-LeCoultre Calibre 758; mechanical automatic movement; 65-hour power reserve; 47 jewels; 340 parts
Features: Hour, minute, small seconds; chronograph: hour and minute counters; central sweep seconds hand; chronograph operating indicator
Case: 42mm; steel; rotating bezel; sapphire crystal; water resistant to 10 bar;
Dial: Matte black; white superluminova hour-markers
Strap: Black leather with steel pin buckle

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