Abstract: A metal tubular connecting part includes a total axial length, an inner surface, and an outer surface. The inner and outer surfaces delimit a wall, an outer transition surface, and an inner transition surface. The outer transition surface and the inner transition surface delimit a transition thickness of the wall. A first threaded end is defined by a first outer surface portion extending over a first axial length. A second threaded end is defined by a second inner surface portion extending over a second axial length. The sum of the first axial length and the second axial length is less than or equal to the total axial length of the connecting part.