Abstract: A false twist apparatus, for processing primarily fine denier yarns at low level twist levels with consistency and good process control, comprises a roller mounted for rotation about its longitudinal axis and input and output guides, to guide the yarn in a helical path around the roller, mounted on a guide support extending adjacent the roller. One of the guides is positionally adjustable on the support in a direction parallel with the roller axis to alter the helix angle of the yarn around the roller and the twist level. For S and Z twist, two drive spindles are provided symmetrically disposed on opposed sides of the support, the roller being secured on the appropriate spindle and the output guide being moved to the appropriate side of the support.