The invention relates to a device for conveying heated air to a person and comprises an air-permeable inner sheet and an air-impermeable outer sheet which are connected to one another by welds in order to form a panel-like shape in the inflated state. The welds produce a main duct having, viewed at the inlet end and in the non-inflated state, a main duct width. The main duct is delimited by at least one first series of elongate first welded strips, the first intermediate spaces which are in line with one another. The length of each of these first intermediate spaces, viewed in the non-inflated state, is in each case smaller than the main duct width. The length of each first welded strip is at least 15% of the main duct width and at most 80% of the main duct width.