An implantable inflatable penile prosthesis cylinder has a longitudinal axis and includes an inflatable portion. The inflatable portion includes a chamber that defines an inflatable chamber. The chamber wall includes at least one thin wall section and at least one thick wall section. The at least one thin wall section stretches a greater amount than the at least one thick wall section in a plane extending perpendicular to the longitudinal axis when the inflatable chamber is transitioned from a deflated state to an inflated state.