Abstract: A cylinder unit includes a cylinder which is closed by a separate bottom. The cylinder is sealed by an annular seal which is accommodated in an annular groove. The annular seal is fixed to the cylinder by a disk element connected to the bottom. The bottom forms a first groove side surface of the annular groove, and the disk element forms a second groove side surface of the annular groove.

Abstract: A piston-cylinder unit has a piston rod at which is arranged at least one piston which has at an outer lateral surface a radially elastic piston ring that moves into a cylinder depending on a stroke position of the piston rod and has a smaller diameter than in a stroke position in which the piston is located outside of the cylinder. The piston ring has a stop that defines a maximum diameter of the piston ring.