A packing layer for a structured packing which has corrugations forming open channels. Each channel includes first and second corrugation peaks bounding a first corrugation valley with each corrugation peak having an apex and the corrugation valley having a valley bottom. A spacer element is mounted on and extends along the apex of at least one corrugation peak. The spacer element has an edge which has a larger normal spacing from the valley bottom than, the spacing of the apex of the corrugation peak from the valley bottom.