Quick coupling for threaded or shaped terminals, comprising: a substantially tubular main body internally delimiting a passage duct for a fluid, wherein said main body has a first end and a second end opposite the first end and configured to connect with a circuit; a plurality of jaws arranged around a main axis (X-X) of the passage duct, wherein the jaws are operatively coupled to the main body at the first end, wherein each of said jaws is movable radially with respect to the main body between a first release position from a terminal and a second position coupled to the terminal; a guide ring coaxial with the main body and having radial guides engaged with the plurality of jaws for guiding them radially during the movement between the first and second position; an obturator substantially tubular and coaxial with the main body, wherein the obturator is movable axially with respect to the main body between an advanced position towards engagement portions of the jaws, in which radially and at least partially overcomes the engagement portions of the jaws to hold them in the first release position from the terminal, and a retracted position, in which it releases the engagement portions and allows the radial movement of the jaws; an auxiliary body sliding axially with respect to the main body, wherein the auxiliary body comprises a ring nut radially external to the main body and movable axially on the main body and a radially internal body with respect to the main body and integrally connected to the ring nut, wherein an operative portion of the radially internal body is engaged or engageable with the jaws; wherein the auxiliary body is movable axially with respect to the main body between a rearward position with respect to the engagement portions of the jaws corresponding to the release position of the jaws, and an advanced position, in which radially pushes the jaws into the second coupled position to the terminal; an engagement/detachment slider coaxial with the main body and movable axially with respect to the main body and with respect to the obturator; latching/releasing elements movable in through holes formed in the main body, wherein said latching/releasing elements are engaged/engageable with the engagement/detachment slider and with the radially internal body; characterized in that it comprises at least a motion transmission rod axially interposed between the engagement/detachment slider and the obturator to transmit an axial movement of the obturator to the engagement/detachment slider. a substantially tubular main body internally delimiting a passage duct for a fluid, wherein said main body has a first end and a second end opposite the first end and configured to connect with a circuit; a plurality of jaws arranged around a main axis (X-X) of the passage duct, wherein the jaws are operatively coupled to the main body at the first end, wherein each of said jaws is movable radially with respect to the main body between a first release position from a terminal and a second position coupled to the terminal; a guide ring coaxial with the main body and having radial guides engaged with the plurality of jaws for guiding them radially during the movement between the first and second position; an obturator substantially tubular and coaxial with the main body, wherein the obturator is movable axially with respect to the main body between an advanced position towards engagement portions of the jaws, in which radially and at least partially overcomes the engagement portions of the jaws to hold them in the first release position from the terminal, and a retracted position, in which it releases the engagement portions and allows the radial movement of the jaws; an auxiliary body sliding axially with respect to the main body, wherein the auxiliary body comprises a ring nut radially external to the main body and movable axially on the main body and a radially internal body with respect to the main body and integrally connected to the ring nut, wherein an operative portion of the radially internal body is engaged or engageable with the jaws; wherein the auxiliary body is movable axially with respect to the main body between a rearward position with respect to the engagement portions of the jaws corresponding to the release position of the jaws, and an advanced position, in which radially pushes the jaws into the second coupled position to the terminal; an engagement/detachment slider coaxial with the main body and movable axially with respect to the main body and with respect to the obturator; latching/releasing elements movable in through holes formed in the main body, wherein said latching/releasing elements are engaged/engageable with the engagement/detachment slider and with the radially internal body; characterized in that it comprises at least a motion transmission rod axially interposed between the engagement/detachment slider and the obturator to transmit an axial movement of the obturator to the engagement/detachment slider.