Abstract: Perforated sheet for a head box of a paper machine, the perforated sheet being provided with a number of parallel flow passages starting from a common front face. The perforated sheet is provided with a set of feeding ducts which can be connected to a source of flushing liquid and which is connected, by means of flushing ducts, to the front face of the perforated sheet. The perforated sheet preferably consists of several rod elements, each of which is provided with a flow passage and which have been assembled as parallel to each other, side by side and one above the other, into an integrated package.