Abstract: A two-phase or mono-phase heat-exchanger for at least one electronic power component wherein the heat-exchanger supports a plurality of heat exchange tubes, each having a heat exchange fluid therein, and wherein said heat-exchanger includes at least one rigid plate provided with zones for receiving portions of the heat exchange tubes and wherein the heat-exchanger includes opposite edges which are formed so as to be secured to edges of adjacent heat-exchangers in such a manner that front and rear surfaces of the at least one rigid plate of each heat exchange unit are coplanar when one heat-exchanger is secured to an adjacent heat-exchanger.