Guillaume Nery is a three-time free dive world record holder and brand ambassador to Ball Watch Company. He makes dives without assistance or equipment on a regular basis to depths of 100 meters (330 feet). This is not only hard to do, it’s hard to see while doing it. The ambient light is about 1% of surface light at these depths.

This is where the 53 micro gas tubes (tritium) come in very handy and why he uses the Engineer Master II Diver GMT watch. The watch has a rotating inner bezel the utilizes 41 of the gas tubes with the remaining 12 being placed on the hands and dial. This illumination setup is very beneficial and allows divers to see their watch at any depth.

The crowns operate underwater to adjust the time or elapsed minutes ring with no problem, which is, of course, crucial to any professional diver. When the crowns are unscrewed red-o-rings are visible which is part of the watertight gasket system that ensures water-resistant down to 300 meters, or 1000 feet.

The movement is automatic caliber ETA 2893-2 and has hours, minutes, sweep seconds, second timezone and date. The case is 42 mm in diameter by 14.3 mm thick. The crystal is an anti-reflective sapphire crystal. The model number is DG1020A- PAJ-BK and costs approximately $2,600.