Abstract: An artificial penis has a cylinder having a cylinder wall enclosing a hollow, a front wall with a first opening and a rear wall with a second opening. A piston rod is guided within the hollow. The piston rod has an initial position in which a first cylinder space is at a maximum and a second cylinder space is at a minimum and an extended position in which the first cylinder space is at a minimum and the second cylinder space at a maximum. A pump supplies a fluid under pressure to move the piston rod in an extending direction. An enclosure having an outer shape of a penis encloses the cylinder and the end of the piston rod. The enclosure has an initial position when the pump is released and an extended position when the pump is actuated.