This is the picture from James's website and the explanations about this watch:

Unique Left Hand Rolex Sea Dweller, made in 1987

The model 16660 was the first sapphire glass version of the Sea Dweller and the first to be rated for 4,000 feet depth capability.

Rolex Geneva records show that it was delivered to the French company COMEX specifically for a diver who wished to wear his watch on his right arm, although the watch bears no COMEX identification.

Rolex produced an unknown number of Datejusts in the 1950s with Left Hand configuration and ten 18k model 1680 Submariners in the late 1970s. However this is the only known sapphire glass watch and the only Sea Dweller known to have been made in this unusual configuration.

I choose to wear it on my left wrist which makes the watch very comfortable as the crown no longer digs into the back of my hand as I type.