An exhaust gas aftertreatment device for an Internal Combustion Engine wherein the exhaust gas aftertreatment device comprises a catalytic converter, wherein the catalytic converter comprises an encapsulating member comprising a first and a second opposing end portions (4;6), and a midsection portion arranged there between, wherein an outside of the encapsulating member defines the outer perimeter of the catalytic converter, and wherein the inside of the encapsulating member defines a converter volume of the catalytic converter, wherein a first catalytic converter substrate and a second catalytic converter substrate are arranged within the converter volume of the catalytic converter, wherein a first port is connected to the first end portion for fluid communication with the converter volume, and wherein within the converter volume, starting from the first end portion, the following is provided in order: • a first volume being defined between the first end portion, and the first catalytic converter substrate, • the first catalytic converter substrate being arranged between the first volume and a subsequently provided second volume, • the second volume being defined between the first catalytic converter substrate and the second catalytic converter substrate, wherein the first volume is in fluid communication with the second volume through the first catalytic converter substrate, • the second catalytic converter substrate being arranged between the second volume and a subsequently provided third volume, and • the third volume being defined between the second catalytic converter substrate and the second end portion, wherein the third volume is in fluid communication with the second volume through the second catalytic converter substrate, wherein the exhaust gas aftertreatment device additionally comprises an exhaust gas guiding means and a pipe member within said encapsulating member, wherein the pipe member is arranged within the second converter substrate and connects the second volume with the third volume for fluid communication, and wherein the exhaust gas guiding means is arranged in the second volume, wherein a first open section of the exhaust gas guiding means is connected to the pipe member and sealed against the pipe member, and a second open section of the exhaust gas guiding means is arranged adjacent the first catalytic converter substrate, wherein the second open section of the exhaust gas guiding means seals against the midsection portion of the encapsulating member such that the second volume is divided into a first part of the second volume and a second part of the second volume, wherein the first part of the second volume is provided adjacent to the first catalytic converter substrate and the second part of the second volume is provided adjacent to the second catalytic converter substrate, wherein a second port is connected to the midsection portion of the encapsulating member for fluid communication with the second part of the second volume, and wherein the cross sectional area of the first open section of the exhaust gas guiding means is smaller than the cross sectional area of the second open section of the exhaust gas guiding means, characterized in that the exhaust gas guiding means comprises a resilient curved section between the first open section and the second open section, which resilient curved section changes degree of curvature when the exhaust gas guiding means changes shape due to change in heat load from the exhaust gas emissions, for hindering excess force on the inside of the encapsulating member. • a first volume being defined between the first end portion, and the first catalytic converter substrate, • the first catalytic converter substrate being arranged between the first volume and a subsequently provided second volume, • the second volume being defined between the first catalytic converter substrate and the second catalytic converter substrate, wherein the first volume is in fluid communication with the second volume through the first catalytic converter substrate, • the second catalytic converter substrate being arranged between the second volume and a subsequently provided third volume, and • the third volume being defined between the second catalytic converter substrate and the second end portion, wherein the third volume is in fluid communication with the second volume through the second catalytic converter substrate,