As with the original version, for serious movement enthusiasts, the big draw is perhaps less the design per se than the configuration of the automatic winding system and the tourbillon. The peripheral winding system is a variation on a standard automatic winding system: an oscillating weight, set in motion by the arm movements of the wearer, winds the mainspring and keeps the watch running. In a conventional automatic winding system, the rotor sits on top of the movement plate, which has two potential disadvantages: first, the rotor adds thickness to the movement; and second, the rotor tends to obscure the view of the movement itself (this is of course assuming the movement is something you would want to look at in the first place).
One possible solution to both problems is to use a micro-rotor, which is set into the movement plate itself; as there are no free lunches in mechanical engineering, this comes with its own set of drawbacks, including a reduction in available space for the barrel, going train, and regulating organs, as well as inherently lower efficiency. Another solution, which is somewhat more rare, is to put the winding weight on the edge of the movement plate and on the same level – this is the so-called peripheral winding system.
from Best Watches For Men https://ift.tt/2OXZHZ5