Abstract: The invention comprises an installation for continuously stamping advancing rolling stock and the like. A pair of cylinders are positioned having their bottom ends facing each other and their top ends extending in substantially opposite directions. Each of the cylinders has a piston movable therein and a piston rod connected thereto. The piston rod of the first of the cylinders is connected to a stamping pendulum, having a stamping die thereon; whereas, the piston rod of the second cylinders is connected to a stationary point. The first cylinder has at the top end thereof a stationary intermediate piece with a passage for the piston rod provided therein. The passage has an internal diameter exceeding the external diameter of the piston rod and a projection located on the piston at the side of the intermediate piece. The projection follows the motion of the piston and sealingly engages the passage during the extension of the piston.