Abstract: A circular cross section, shielded electrical connector adaptor (8) comprises a metal shell (54), in which is fitted frictionally, a dielectric plug (70) having a central bore (72) in which an elongate rectilinear electrical contact element (82) is fitted frictionally. The shell (54) has at each end thereof a peripheral, external screwthread (56,58). The contact element (82) has a pin portion (86) at one end and a receptacle portion (90) at its other end. The screwthreads (56 and 58) can be meshed with internal screwthreads (28 and 40) of a shielded plug connector part (4) and a shielded jack connector part (6) to provide a double ended, shielded electrical connector (2) having a plug at one end and a jack at the other end. The contact element may be provided with pin portions (86) or receptacle portions (90) at both ends, for producing a connector with a plug at both ends or a jack at both ends, respectively.