A vibration damper has a cylinder filled with damping medium. In the cylinder, a piston rod with a piston is realized so that the piston can move axially. The piston divides the cylinder into two working chambers. The vibration damper also has a damping valve. The damping force of the damping valve can be changed by a magnetic force generated by a magnetic coil inside a magnetic return body on an armature against a spring force of at least one spring. At least two regulating or adjustment parameters are provided to set at least two characteristics which differ from one another in terms of different flows to the magnetic coil. The characteristics can be set by a change of the effective spring characteristic with reference to a damping valve stroke position of the damping valve and also by the ability to regulate the magnetic conductivity of the magnetic return body by an actuator. The actuator can have a magnetic constriction, to which constriction a magnetic conductor body can be connected in parallel.