Exhaust system for an internal combustion engine, comprising an exhaust gas treatment unit, which is carried at a carrier structure and which is elongated in the direction of an exhaust gas treatment unit longitudinal axis, wherein: - a receiving opening with an opening central axis for receiving the exhaust gas treatment unit in the carrier structure and a first sealing surface enclosing the opening central axis in a ring-like manner are provided at the carrier structure, - a second sealing surface enclosing the exhaust gas treatment unit longitudinal axis in a ring-like manner is provided at the exhaust gas treatment unit, wherein the second sealing surface is located opposite the first sealing surface when the exhaust gas treatment unit has been received in the carrier structure, - a third sealing surface enclosing the exhaust gas treatment unit longitudinal axis in a ring-like manner is provided at the exhaust gas treatment unit, and - a closing element, which can be fixed together with the exhaust gas treatment unit to the carrier structure is provided with a fourth ring-like sealing surface, wherein the fourth sealing surface is located opposite the third sealing surface when the closing element has been fixed together with the exhaust gas treatment unit to the carrier structure, wherein a first sealing element is arranged between the first sealing surface and the second sealing surface, a second sealing element is arranged between the third sealing surface and the fourth sealing surface, characterized in that the first sealing element and the second sealing element are of identical design to each other, and that the first sealing element and the second sealing element have a ring-like sealing element body, wherein inner clamping sections protruding in a radially inward direction are provided at an inner circumferential area of the sealing element body and outer clamping sections protruding in a radially outward direction are provided at an outer circumferential area of the sealing element body and that the first sealing element is clamped with its inner clamping sections at the exhaust gas treatment unit, and that the second sealing element is clamped with its outer clamping sections at the exhaust gas treatment unit. - a receiving opening with an opening central axis for receiving the exhaust gas treatment unit in the carrier structure and a first sealing surface enclosing the opening central axis in a ring-like manner are provided at the carrier structure, - a second sealing surface enclosing the exhaust gas treatment unit longitudinal axis in a ring-like manner is provided at the exhaust gas treatment unit, wherein the second sealing surface is located opposite the first sealing surface when the exhaust gas treatment unit has been received in the carrier structure, - a third sealing surface enclosing the exhaust gas treatment unit longitudinal axis in a ring-like manner is provided at the exhaust gas treatment unit, and - a closing element, which can be fixed together with the exhaust gas treatment unit to the carrier structure is provided with a fourth ring-like sealing surface, wherein the fourth sealing surface is located opposite the third sealing surface when the closing element has been fixed together with the exhaust gas treatment unit to the carrier structure,