Boncinni worked with Cousteau at CEMA (Centre d’Etudes Marines Avanceds) from 1968-1972, and was also a COMEX engineer. Now the watch, which is being offered by his family, is a prototype, meaning that it is hard to compare it to any existing Ploprof of its time. When it comes to prototypes, anything goes. I say this because this watch has one defining feature which separates it from its counterparts, and that is the orientation of the crown. The Ploprof is known for having the crown on the left side of the watch, although it is still technically a right-handed watch (this feature existed to aid in one-handed operation of the bezel). You could write this watch off at first glance and call it a fake due to the reversed orientation of the crown. Conversely, you could see this watch for what it is, a one-off prototype owned by a true, dyed-in-the-wool, professional diver. Like I said, with prototypes, you just never know.