Press-fit connection comprising: a press fitting (10, 10', 10"), in turn comprising a main body (12, 12', 12") which defines and delimits a fluid flow channel in its interior, the main body (12, 12', 12") having a first and a second end at which the fluid flow channel opens to an outer side, the first end of the press fitting (10, 10', 10") being designed as a male press-fit connection piece which is designed to be introduced at least partially into a superordinate pipe piece, in particular made of plastics material, which is not part of the press fitting (10, 10', 10") according to the invention, in order to serve this pipe piece as support body arranged therein for pressing the pipe piece with the press fitting (10, 10', 10"), the second end of the press fitting (10, 10', 10") being designed as a female press-fit connection piece which is designed to provide a pipe piece for pressing with a further press fitting, the press fitting (10, 10', 10") comprising a pressing sleeve which is arranged on the main body (12, 12', 12") in such a way that it at least partially surrounds the first end of the main body (12, 12', 12"), and the main body (12, 12', 12") being made of plastics material, characterised in that the press-fit connection further comprises: a further fluid line, which comprises a pressing sleeve and a support body arranged radially therein, the further fluid line being arranged at the second end of the press fitting (10, 10', 10") in such a way that the support body is arranged radially inside the second end of the press fitting (10, 10', 10") and the pressing sleeve of the further fluid line surrounds both the support body and the second end of the press fitting (10, 10', 10") radially on the outside, so that the fluid flow channel is continued through the further fluid line in the region of the second end of the press fitting (10, 10', 10"). a press fitting (10, 10', 10"), in turn comprising a main body (12, 12', 12") which defines and delimits a fluid flow channel in its interior, the main body (12, 12', 12") having a first and a second end at which the fluid flow channel opens to an outer side, the first end of the press fitting (10, 10', 10") being designed as a male press-fit connection piece which is designed to be introduced at least partially into a superordinate pipe piece, in particular made of plastics material, which is not part of the press fitting (10, 10', 10") according to the invention, in order to serve this pipe piece as support body arranged therein for pressing the pipe piece with the press fitting (10, 10', 10"), the second end of the press fitting (10, 10', 10") being designed as a female press-fit connection piece which is designed to provide a pipe piece for pressing with a further press fitting, the press fitting (10, 10', 10") comprising a pressing sleeve which is arranged on the main body (12, 12', 12") in such a way that it at least partially surrounds the first end of the main body (12, 12', 12"), and the main body (12, 12', 12") being made of plastics material, characterised in that the press-fit connection further comprises: a further fluid line, which comprises a pressing sleeve and a support body arranged radially therein, the further fluid line being arranged at the second end of the press fitting (10, 10', 10") in such a way that the support body is arranged radially inside the second end of the press fitting (10, 10', 10") and the pressing sleeve of the further fluid line surrounds both the support body and the second end of the press fitting (10, 10', 10") radially on the outside, so that the fluid flow channel is continued through the further fluid line in the region of the second end of the press fitting (10, 10', 10").