a leaf spring takes the form of a slender arc-shaped length of spring steel of rectangular cross-section. in the most common configuration, the center of the arc provides location for the axle, while loops formed at either end provide for attaching to the vehicle chassis. for very heavy vehicles, a leaf spring can be made from several leaves stacked on top of each other in several layers, often with progressively shorter leaves. leaf springs can serve locating and to some extent damping as well as springing functions. while the interleaf friction provides a damping action, it is not well controlled and results in stiction in the motion of the suspension. for this reason, some manufacturers have used mono-leaf springs.