The connector (1) has a connector body (2) comprising a through bore (11), and a male member (7) releasably fixable in the through bore by a retainer (6). The retainer comprises a ring body (5), and a locking element (10) has an annular body. The ring body and the annular body circulate around the male member and/or the coupling body. The locking element is moved from a free position to a locking position in an axial direction with respect to the through bore when the male member is secured in the through bore with the holder. The holder and/or the locking element is made from plastic.