At first glance, ebm-papst diagonal fans differ only slightly from axial fans. The air is drawn in axially, but the outflow is diagonal. With diagonals fans, the conical shape of the impeller and housing results in greater compression of the intake air. The outstanding feature of this type of fan as compared to axial fans of the same size and offering similar performance is a far lower operating noise level at high pressures. They are particularly suitable for applications involving intensive cooling with a high component concentration.