Five chassis mounting points, two for the lower A-arm, one for each link of the upper "virtual A-arm", and one for the toe link.

Four upright mounting points, one for the lower A-arm, one for each link of the upper "virtual A-arm", and one for the toe link.

In the PorscheGT3 rear suspension the lower lateral link and the lower trailing link act as a lower A-arm, with two chassis mounting points and a single upright mounting point. The pair of angled (in plan view) upper links converge to form a “virtual” A-arm, and the toe control link controls the toe.

In the case of the PorscheGT3, the lower A-arm is implemented as a trailing link connecting part way along the lateral link. However, for calculation purposes, the lower link lengths need to be specified as the distance from chassis pivot to the upright pivot.