An occlusion device for treating an aneurysm can have an inner embolic device with a proximal section and a distal section. The distal section has a first stiffness and the proximal section has a second stiffness. Further, the device has an expandable mesh capable of a collapsed position and an expanded position. The mesh can be disposed over, and attached to, a portion of the proximal section of the inner embolic device. The first stiffness is greater than the second stiffness and the inner embolic device comprises a preselected shape which assists in transforming the expandable mesh from the collapsed position to the expanded position.
