Right and left screw

a screw having threads upon the opposite ends which wind in opposite directions.

See also: Screw

References in periodicals archive ?
A further highlight of the new ScrewCon 3 software is the simultaneous on-screen display of right and left screws of the twin-screw extruder.
A further highlight of the ScrewCon 3 software is the simultaneous on-screen display of right and left screws of the twin-screw extrader.