A seal assembly includes an outer member defining a bore and an inner member received in the bore of the outer member and one of the outer member and the inner member defining a shoulder portion. An inner circular cross-section metallic ring member and an outer circular cross-section metallic ring member are disposed between the outer member and inner member and against the shoulder portion. A wedge member engages the inner circular cross-section metallic ring member and the outer circular cross-section metallic ring member for applying an axial force against each of the inner and outer circular cross-section metallic ring members in a direction toward the shoulder portion and for applying a radially outer force against the outer circular cross-section metallic ring member and for applying a radially inner force against the inner circular cross-section metallic ring member.