Mark in Paris[Purist]
10488
I don't know for the strap's size
as I couldn't see the watch already.
In fact, the aim was to provide a thinner Tourbillon as the square RM017 provided already, but in the Tonneau-shaped case. The RM67-01 had already opened the way and it was logical to go that way for RM.
However, I don't know if they strictly picked up the RM67's case or if they selected the RM010's, with a thinner caseband to achieve this result.
I imagine the answer would be in the more or less rounded bezel: the RM67-01's bezel is significantly flatter (except at the ends). I imagine the thinner the case, the flatter it has to be, hence the RM67's direction imho.
Best, Mark