Abstract: A tower (A) for effecting heat transfer or chemical reactions contains a packing (B) formed from a multitude of packing elements (2, 28). Each element includes a peripheral wall (10, 30) and a convoluted interior wall (12, 32) that spirals inwardly from the peripheral wall toward the center of the element, thus forming a convoluted passage (14, 34) through the element. The convoluted passages in the elements capture the flow of fluid through the packing so that less fluid follows voids between the elements and more flows through the elements. Moreover, the convoluted interior wall of each element provides a large surface area for heat transfer or chemical reactions.