Abstract: A cooling system for electronic component cases is disclosed. The system includes a fan diffuser located between the exhaust fan and the exhaust grill formed in an exterior wall of the case. The diffuser allows the grill to vary in both size and shape from the fan, thus allowing the grill footprint to differ from that of the fan. This arrangement allows the grill size to be optimized, taking advantage of the available space on the case wall. The diffuser also allows components to be located between the fan and the case wall portion where the grill is located.