A drywall head for applying mastic compound or other similar material to an outside corner edge of two adjoining drywall board sections to cement on a taped-on corner during drywall assembly. The laser generates an output beam that is directed along a beam axis. The spatial orientation of the airway is manipulated, directly or indirectly, to affect the configuration of the airway. The inner turbine rotor is configured to rotate in an opposite direction about the axis of rotation from the outer turbine rotor.