An electrical connector device (1), which extends along a longitudinal axis (X) and having an interface part (2) comprising a first set (3) of electrical contact elements (3a, 3b, 3c, 3d) arranged along a first line (L1), which is orthogonal to the longitudinal axis (X). The connector device (1) comprises mechanical engagement elements (17, 18, 19) being shaped such that the electrical connector device (1) can be electrically and mechanically connected with an identical connector device (1) when they are aligned along the longitudinal axis (X) and one of them rotated 180 degrees about a transversal axis (Y) parallel with the first line (L1). The interface part (2) comprises a second set (4) of electrical contact elements (4a, 4b, 4c, 4d) and a third set (5) of electrical contact elements (5a, 5b, 5c, 5d). The second and third sets (4, 5) are symmetrically arranged on opposite sides of the first line (L1) in a first plane (P1) through the first line (L1), such that for each contact element (4a, 4b, 4c, 4d) of the second set (4) there is a corresponding contact element (5a, 5b, 5c, 5d) of the third set (5), which is arranged with equal distance to the first line (L1). Each contact element (4a, 4b, 4c, 4d) of the second (4) set is electrically connected to its corresponding contact element (5a, 5b, 5c, 5d) of the third set (5).