An electrical switch, comprising: a tubular housing having a conductor receiving end and an operating end opposite the conductor receiving end, wherein the tubular housing includes an interface positioned intermediate the conductor receiving end and the operating end; an operating rod extending through the operating end toward the conductor receiving end; a fixed contact electrically coupled to the conductor receiving end; a moveable contact electrically coupled to the interface and the operating rod, wherein the moveable contact is moveable between a first position contacting the fixed contact and a second position separated from the fixed contact; and a diaphragm positioned in the tubular housing between the interface and the operating end to prevent voltage from the interface from arcing to the operating end, wherein the diaphragm includes a bore therethrough for receiving the operating rod, wherein the diaphragm includes a first tubular portion and a second tubular portion having an outside diameter smaller than an outside diameter of the first tubular portion, and a shoulder portion between the first tubular portion and the second tubular portion, wherein the first tubular portion of the diaphragm comprises an inner annular groove adjacent the shoulder portion, wherein the first tubular portion is frictionally engaged with an inside of the tubular housing and the second tubular portion is frictionally engaged with the operating rod, and wherein movement of the operating rod from the first position to the second position causes the second tubular portion to move relative to the first tubular portion, the movement deforming the shoulder portion. a tubular housing having a conductor receiving end and an operating end opposite the conductor receiving end, wherein the tubular housing includes an interface positioned intermediate the conductor receiving end and the operating end; an operating rod extending through the operating end toward the conductor receiving end; a fixed contact electrically coupled to the conductor receiving end; a moveable contact electrically coupled to the interface and the operating rod, wherein the moveable contact is moveable between a first position contacting the fixed contact and a second position separated from the fixed contact; and a diaphragm positioned in the tubular housing between the interface and the operating end to prevent voltage from the interface from arcing to the operating end, wherein the diaphragm includes a bore therethrough for receiving the operating rod, wherein the diaphragm includes a first tubular portion and a second tubular portion having an outside diameter smaller than an outside diameter of the first tubular portion, and a shoulder portion between the first tubular portion and the second tubular portion, wherein the first tubular portion of the diaphragm comprises an inner annular groove adjacent the shoulder portion, wherein the first tubular portion is frictionally engaged with an inside of the tubular housing and the second tubular portion is frictionally engaged with the operating rod, and wherein movement of the operating rod from the first position to the second position causes the second tubular portion to move relative to the first tubular portion, the movement deforming the shoulder portion.