Anti-unscrewing quick coupling fitting

A quick coupling fitting comprising:

• a first connector comprising a first thread;
• and
• a second connector comprising a second thread that is screwed with the first thread of said first connector, said second connector penetrating said first connector co-axially along a longitudinal axis (L) and frontally allowing a fluid to pass through the quick coupling fitting when said quick coupling fitting is in a fully screwed position,
• wherein said first connector includes an external casing, a sliding ring slidably axially mounted onto the external casing, and a screwing ring,
• wherein said second connector includes an external body, a locking ring axially mounted onto the external body and rotatably onto the external body about the longitudinal axis (L),
• wherein the sliding ring includes at least one tooth that extends from an annular end of the sliding ring facing towards said second connector,
• wherein the locking ring includes at least one housing that extends from an annular end of the locking ring facing towards said first connector,
• wherein the at least one tooth is able to engage the at least one housing providing a fully screwed position of the quick coupling fitting allowing a fluid to pass through the quick coupling fitting,
• wherein said first connector further comprises at least one guide track integral with the external casing and disposed along the longitudinal axis (L), such that the sliding ring is able to slide along the at least one guide track, which is able to prevent any rotation of the sliding ring about the longitudinal axis (L),
• wherein the screwing ring is screwed onto said external casing, and
• wherein, when the quick coupling fitting is in the fully screwed position, the sliding ring is suitable for passing from a sliding configuration to a locking configuration in which the screwing ring blocks the sliding of the sliding ring, thus providing an unscrewing locking of the quick coupling fitting in the fully screwed position.