Abstract: An electronic module which provides for the insertion of printed circuit cards into the card receptacles of a heat exchanger with essentially zero insertion force. The printed circuit cards are of the type wherein individual electrical components are mounted on printed wiring boards with the body of the components in physical contact with thermally conductive strip members also located on the printed circuit board. These strip members terminate at the edge of the board at which is located an edge strip, also formed from a thermally conductive material. The edge strip is arranged to cooperate with a surface of a heat exchanger. A plurality of springs are provided for normally urging the edge strip against this surface. When it is desired to insert or remove a printed circuit card, the springs are compressed in unison so as to allow free ingress and egress to the card receptacle.