A parallel optical transceiver module is provided that has a heat dissipation system that dissipates large amounts of heat, while also protecting the laser diodes, ICs and other components of the module from particulates, such as dust, for example, and from mechanical handling forces. The heat dissipation system is configured to be secured to the optical subassembly (OSA) of the module such that when the OSA is secured to the upper surface of the leadframe of the module, the OSA and the heat dissipation system cooperate to encapsulate at least the laser diodes and laser diode driver IC in a way that protects these components from dust and other particulates and from external mechanical forces. The heat dissipation system of the module is disposed for coupling with an external heat dissipation system, e.g., with a heat dissipation system that is provided by the customer.