Systems, methods, techniques and apparatuses of contactors are disclosed. One exemplary embodiment is a contactor including an electric pole, a pair of plungers, and a pair of opening springs. The electric pole includes a fixed yoke member and a movable yoke member arranged respectively at a proximal position and a distal position with respect to a movable contact. The fixed yoke member includes a pair of through holes. The pair of second plungers are inserted in a corresponding through hole passing through the fixed yoke member and symmetrically positioned with respect to a main symmetry plane of the contactor, which is parallel to a displacement axis of the movable contact and perpendicular to a displacement plane of the movable contact. The pair of opening springs are symmetrically positioned with respect to the main symmetry plane.