The invention relates to a screw element comprising an internal torque limitation for fastening a liquid-conducting line to a device connector or to a coupling for a further line, said screw element having a connection part, which preferably has a thread, and an actuation part; and having a torque limiting unit that limits a torque that can be transmitted from the actuation part to the connection part, wherein the torque limiting unit is arranged between the connection part and the actuation part and has a limiting element, in particular a separate limiting element, that can be assembled from at least two limiting element parts connectable to one another and that limits the torque limiting unit in an axial direction of a longitudinal axis of the screw element. The invention further relates to a system comprising at least one screw element and a line fastened to the screw element.