Hu-Friedy's Clear Collection consists of innovative instruments designed to accent, individualise and optimise the biomechanics of the 'invisible' aligner experience. The Vertical emphasises over-correction of rotations by producing an indentation at the mesial or distal line angles on the facial and/or lingual of a specific tooth. A rotational couple can also be created using vertical indents on facial and lingual surfaces on opposing sides of the tooth. Also used to produce an indent, introducing a mild 'nudge', to enhance resolution of in-and-out discrepancies.