To allow inversion deformation of a contact board and restoration from it using spring force, allow a contact to reliably make contact and separation, and to increase a contact opening speed.

A switch 1 comprises a movable contact 15 that is made to contact and separate a fixed contact 5 for supplying and interrupting a load current, a contact board 13 where the movable contact 15 is provided, and a steel ball 31 that is resiliently contacted to the contact board 13 for changing the resiliently contacted position to the contact board 13 by the operation of a switch knob. Thus, the contact board 13 is displaced to attach/retract the movable contact 15 to the fixed contact 5. In the switch 1, the contact board 13 is formed by an inverting spring that can be inverted and deformed. Contact board support sections 11, 19 for supporting the contact board 13 at both the sides of the movable contact 15 are provided in a housing 3. The steel ball 31 travels to the contact board 13 and displaces the contact board 13 by inversion deformation and restoration from it between contact board support sections 11, 19 for allowing the movable contact 15 to attach and retract the fixed contact 5.