an endoluminal prosthesis including a radially expandable support member having interior and exterior surfaces and a wall with openings , a first covering member including a biocompatible polymer material at least partially positioned against the interior surface , and a second covering member including a biocompatible polymer material at least partially positioned against the exterior surface . the first covering member attaches to the second covering member at predetermined bonding locations within less than all of the openings thereby leaving unbonded regions .