This past morning in Skinner auction activity, I was bidding on a curious on 18K Vacheron Constantin pocket watch. I should have bid more but I throw in too much money on pocket watches recently. So I underbid while I did not recognize the secret of this curious escapement on a Vacheron Constantin! From the pictures attached, I do not know much on the setting of the detent and how it would work? Someone has ever seen any similarity or has the intuition about the mechanism 'echappement a Refsort or Prejsort or Rejsort'? What does it mean by the French word xxxsort' anyway? I presume someone on the forum must also bid/win or indeed with better knowledge. Thank you for advise! At least I may learn something even without owning the watch.