I found this statement in the seller's promotional blurb to be a bit of an over-reach:
"Yesterday, in anticipation of selling, I had the crown and pushers replaced, as well I had the watch inspected and regulated to COSC standards."
What's bothersome is that there is an implication that the watch conforms with the COSC chronometer standard for timekeeping precision, thus leading a prospective buyer to believe that the watch is more precise than it may actually be. I'm going to give the seller the benefit of the doubt and presume that what he/she actually means is that on the day that the watch was taken into the shop to have the crown and pushers replaced, it was also regulated such that its apparent daily timekeeping variation fell somewhere in the -4 to +6 sec/day range. It's certainly possible that a randomly selected Cal. 861 movement could indeed meet the COSC chronometer standard, but to make that claim in a way that is credible for a specific watch (one which was not initially COSC certified at the time of manufacture), it would have to be subjected to the 15-day, multi-position, multi-temperature test specified in the ISO 3159:2009 standard.
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