a quick - coupling device for circuits circulating fluids under pressure comprising a socket and a fitting element that can be housed in the socket , the socket including an outer body defining at least part of a first channel and comprising an annular cavity opening on the first channel , a substantially annular constraint element at least partly housed in the annular cavity and movable therein , and including a plurality of constraint sectors made up of circular sectors of the constraint element , moved radially and defining a release position wherein the constraint element is retracted into the groove so as to enable the fitting element moving relative to the socket , and a tightening position at which the constraint element secures the fitting element to the socket , an extractor partly housed in the outer body able to move the constraint element from the tightening position to the release position .