Abstract: A clamping device for use with a gas spring in the form of a cylinder containing a gas, and a piston and piston rod movable within the cylinder. The clamping device is secured to the end of the cylinder through which the piston rod passes, and includes a clamping portion that engages and clamps around the piston rod to provide resistance to movement of the piston rod relative to the cylinder. The clamping device is a U-shaped structure having clamping legs that can be moved toward each other by a bolt and nut arrangement. The clamping device can be made from an injection molded plastic material, and the device permits continued use of the gas spring after the gas pressure has diminished to a level at which replacement of the spring would otherwise be required.