An occlusive medical implant having a frame actuatable between a collapsed delivery configuration and an expanded implanted configuration, the frame including a generally tubular portion with a threaded insert configured to removably attach to a threaded distal end of a core wire; an occlusive element disposed on the frame; where a proximal portion of the occlusive element and the proximalmost extent of the threaded insert are substantially coplanar with a plane defined by three or more proximalmost extents of the frame in the expanded implanted configuration.