until coming into contact with the wires or felts running over the rolls this then leads to improved stability in the free flow jet and thus to an improvement in paper quality due to the rigid lamella tip 12 and the resulting means of providing different suspension flow rates in the two chambers nozzle areas 3 4 there is an improvement in paper quality in the operating mode for u201c same pulp types u201d in both chambers and very good separation covering of the layers in the operating mode for u201c different pulp types u201d in both chambers compared with single layer and multi layer headboxes with flexible partition elements at the nozzle area outlets which do not permit any difference between the two pulp layers fig4 shows a detail of the slice gap in fig1 the difference in size between the slice gaps a nozzle area 3 and b nozzle area 4 is clearly shown here fig2 now shows a three layer headbox where the suspension is fed into the device through three channels 1 simultaneously at right angles to the machine direction then the direction of flow is turned through 90 degrees into the machine direction the suspension then flows through three turbulence chambers 2 into the outlet chambers known as nozzle areas 3 4 5 at the end of which it leaves the device and enters the dewatering machine here the suspension is injected into the gap between two wires which run.