A delivery system comprises an occlusion device (100, 200) having a proximal portion adjacent a proximal end (114, 208) and a distal portion adjacent a distal end (116, 210). The distal portion has flexibility suitable to function as a guide wire. A delivery catheter (256) is slidably disposed over the proximal portion of the occlusion device so that the distal portion remains exposed when the occlusion device and delivery catheter are advanced within a body lumen. The occlusion device is expandable from a low profile configuration within the delivery catheter to a deployed configuration when deployed from the catheter.
