Abstract: Mechanism for movably supporting a load, comprises a fixed frame, a pendulum lever pivotally connected at one end to the frame, and a link pivotally connected at one end to the other end of the pendulum lever. The other end of the link is connected to a vertically movable load support. A gas spring is pivotally interconnected between the frame and the link at points spaced from the points of articulation of the link and pendulum lever to the frame and to each other. Provision is made for adjusting the position of the pivotal connection between the link and the gas spring lengthwise of the link, and for adjusting the position of the pivotal connection of the gas spring to the frame in a direction toward or away from the point of articulation of the pendulum lever to the frame. Guides for the load are provided, comprising rollers mounted on the frame in between which a vertical member slides vertically.