A torsion spring, typically steel, connecting the left and right wheels (or suspension components) of a vehicle. Its primary function is to resist body roll during cornering. When a vehicle turns, the body tends to lean outwards due to inertia. This component links opposing wheels through flexible connections, mitigating this leaning effect and improving stability.
The device enhances vehicle handling and control, particularly in turns. By reducing the degree of body lean, it keeps the tires in more direct contact with the road surface, which maximizes grip and handling performance. Historically, such components were initially incorporated into performance vehicles to increase speed through corners. They’ve since become standard in most passenger automobiles due to their positive impact on safety and drivability.