Rolex Yachtmaster-ii
The original Rolex Yacht-Master was essentially a luxury version of the Submariner.
Although it had a regatta-inspired name, the original rendition did not
possess any special complications or features that catered to the world
of yacht racing.
Rolex must have realized this oversight, because in 2010 they released
an entirely new line of watches specifically intended for regattas: the Yacht-Master II . 
Unlike the first Yacht-Master that shared many components with Rolex's Submariner line of watches, the Yacht-Master II was an entirely new design. At the heart of the watch beats a caliber 4161 movement, which gives the Yacht-Master II the world's first programmable countdown with a mechanical memory.

Once the countdown has been initiated, it can still be adjusted, entirely on the fly. This allows sailors to synchronize their watch with the official race clock to ensure maximum accuracy. Unlike the design of most other watches, the rotating bezel on the Yacht-Master II is actually connected to the movement inside, allowing it to function as the control interface for the adjustable countdown.

New Rolex Yacht-master II Reference 16655

Everose Stainless Steel Yachtmaster-II

Yellow Gold Stainless Steel Yachtmaster-II

Stainless Steel Yacht-Master 116680
While the first rendition of the Yacht-Master lacked any features specifically intended for boat racing, the Yacht-Master II's regatta countdown complication makes it about as niche of a sports watch as one can find. Overall, the Yacht-Master II is luxurious, playful, and larger-than-life – just like the sport for which it was created.
