Packing arranged for an exchange of heat and/or material

A stacked packing column for heat and/or mass transfer has individual horizontal layers including a lower layer that has a greater density that initiates an accumulation, in particular flooding, and that is 1.5 to 10, preferably 2 to 3 times, greater than the density of an overlying upper layer. The upper layer forms oblique flow channels having lower sections that are more vertically aligned than respective upper sections. The lower sections of the flow channels have a larger cross section than the upper sections, and the sections of larger cross section open into the lower layer.