Abstract: An improved headbox for a papermachine is provided wherein a pair of lobed rotors which extend the full width of the headbox are mounted for delivering paper making stock to rotation in the headbox. As the rotors are rotated, the lobes create a pumping action which withdraws the paper making stock from the distributor manifold and delivers it to the discharge nozzle of the headbox. Simultaneously, the lobes, acting in concert with a closely fitted housing also located within the headbox introduce a shear force on the paper making stock which produces high intensity small scale turbulence in the stock. In this regard, the lobed rotors perform two functions, (1) to deliver a uniformly metered quantity of paper making stock to the slice region, and (2) to impose a high intensity shear field on the stock to break up the flocculation that normally occurs.