Connector, which comprises: a first connector piece (10), and a second connector piece (40) that can be connected to the first connector piece (10) in a fluid-tight manner, where as a connector closure element, to block the two connector pieces (10, 40) against each other, one of the connector pieces (10, 40) is provided with a housing (43) and the other of the connector pieces (10, 40) is provided of a projection (33) that can be inserted into the housing (43) for blocking, the projection (33) or the housing of the first connector piece (10) is arranged in an additional piece (30), preferably in a piece additional (30) in the form of a ring or in the form of a sleeve, which can be guided by a section of the first connector piece (10) and can be fixed therein, and a sealing element (20) that can be opened, in particular a partition or a sealing disk that, in the closed state, acts by blocking the flow for e l connector, characterized in that the additional part (30) has a pressure surface (35) with which it, in a state held on the first connector, pushes the sealing element (30) against a sealing surface (16) of the first connector piece (10), to fix the sealing element (20).Conector, el cual comprende: una primera pieza de conector (10), y una segunda pieza de conector (40) que puede conectarse a la primera pieza de conector (10) de forma estanca al fluido, donde como elemento de cierre del conector, para bloquear las dos piezas de conector (10, 40) una contra otra, una de las piezas de conector (10, 40) está provista de un alojamiento (43) y la otra de las piezas de conector (10, 40) está provista de un saliente (33) que puede introducirse en el alojamiento (43) para el bloqueo, el saliente (33) o el alojamiento de la primera pieza de conector (10) está dispuesto en una pieza adicional (30), preferentemente en una pieza adicional (30) en forma de anillo o en forma de manguito, la cual puede ser guiada mediante una sección de la primera pieza de conector (10) y pue
