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Position and orientation tolerances, such as this perpendicularity tolerance, that are associated with the size dimension apply to the axis of the Unrelated Actual Mating Envelope (UAME). [ASME Y14.5-2009 Para 4.11.4(d) & 7.3.3.1(b) and ASME Y14.5-2018 Para 7.11.4(e) & 10.3.3.1(b).]