A switch characterized by a stationary contact element joined to a stationary contact, a movable contact element joined to a movable contact in a facing relationship to said stationary contact element, a first metallic arc extinguishing plate formed of a U-shaped vertical wall and disposed with its open end facing toward a tip of said stationary contact and which surround said stationary contact element, and a second metallic arc extinguishing plate disposed in parallel to and at the remote side from said contact elements of said first metallic arc extinguishing plate, said first metallic arc extinguishing plates being disposed at predetermined gaps relative to said stationary contact.