[Mayhem]

"A four-link uses four mounting points on the axle and four on the frame (two on each side). At each mounting point, aircraft-style rod ends provide movement at various angles. The result? The four-link system improves how the suspension works in all sorts of driving conditions.

There are primarily two types of four-links: parallel and triangulated. Both styles of four-link accomplish the same thing, which is to hold the axle in the vehicle. The function of a four-link is to keep the rear axle in its proper place under the vehicle, even under hard acceleration or cornering. The bottom two links keep the axle in place front to back. The upper two links keep the axle from rotating and keeps the pinion angle constant. In a triangulated four-link, the upper bars also keep the rear end centered under the car so a Panhard rod isn't needed." -HR

<span style="font-weight: bold">Some might still want to call these ladder bars, or 3-link, per the picture. But with the diagonal strut.</span>