Abstract: Stock flow alignment means for the headbox of a paper machine or the like comprises a plurality of composite tubes having their opposite ends mounted in apertures in two spaced apart tube plates extending in the cross machine direction. Each composite tube includes first and second tubular elements assembled in telescoping relation to accommodate changes in length resulting from thermal expansion. Also, each composite tube is formed with a stepwise enlargement of its cross section in the direction of flow near the telescoped ends of the tubular elements. Flow deflector means disposed in the flow paths to the inlet ends of the composite tubes prevent fibers in the stock from collecting at the inlets.