A device for insertion into a body lumen, comprising: an electrode assembly strip with exposed electrodes, wherein the electrode assembly strip comprises: a polymeric substrate having an upper surface and an opposed lower surface; one or more of substantially flat electrodes disposed over a portion of the upper surface of the polymeric substrate; one or more of electrical traces disposed over a portion of the lower surface of the polymeric substrate in electrical communication with the one or more electrodes by way of metal plated holes through the substrate; a polymeric covering disposed over the one or more electrical traces and portions of the lower surface of the substrate not having the one or more electrical traces thereon; and characterized in that a flexible polymeric tube having opposed open ends (200, 202) defining an open lumen therein between and an inner tubular surface and an outer tubular surface defining a tubular wall therein between; an elongate tubular member having a lumen, a proximal end and a distal end; one or more flexible splines having proximal portions, distal portions and medial portions therein between, wherein the one or more splines comprise an outer surface, an inner surface and two side surfaces (194, 196); an anchor for securably affixing the proximal portions of the one or more splines, wherein the anchor is securably affixed within the lumen of the elongate tubular member at the distal end of the elongate tubular member; and a tip for securably affixing the distal portions of the one or more splines; wherein the electrode assembly strip is compressingly and thermally bonded to the outer surface of the flexible polymeric tube to define a flexible electrode assembly strip; wherein the flexible electrode assembly strip is disposed over at least one of the one or more splines; wherein the flexible polymeric tube comprises a polyether block amide material; wherein the electrode assembly strip is compressed into the tubular wall of the flexible polymeric tube to provide a substantially smooth and atraumatic overall outer surface for the flexible electrode assembly strip; wherein substantial portions of the substantially flat electrodes remain substantially flat to provide substantially flat exposed electrodes; and wherein the electrode assembly strip has a thickness from 0.0005 inches to about 0.008 inches. an electrode assembly strip with exposed electrodes, wherein the electrode assembly strip comprises: a polymeric substrate having an upper surface and an opposed lower surface; one or more of substantially flat electrodes disposed over a portion of the upper surface of the polymeric substrate; one or more of electrical traces disposed over a portion of the lower surface of the polymeric substrate in electrical communication with the one or more electrodes by way of metal plated holes through the substrate; a polymeric covering disposed over the one or more electrical traces and portions of the lower surface of the substrate not having the one or more electrical traces thereon; and a polymeric substrate having an upper surface and an opposed lower surface; one or more of substantially flat electrodes disposed over a portion of the upper surface of the polymeric substrate; one or more of electrical traces disposed over a portion of the lower surface of the polymeric substrate in electrical communication with the one or more electrodes by way of metal plated holes through the substrate; a polymeric covering disposed over the one or more electrical traces and portions of the lower surface of the substrate not having the one or more electrical traces thereon; and characterized in that a flexible polymeric tube having opposed open ends (200, 202) defining an open lumen therein between and an inner tubular surface and an outer tubular surface defining a tubular wall therein between; an elongate tubular member having a lumen, a proximal end and a distal end; one or more flexible splines having proximal portions, distal portions and medial portions therein between, wherein the one or more splines comprise an outer surface, an inner surface and two side surfaces (194, 196); an anchor for securably affixing the proximal portions of the one or more splines, wherein the anchor is securably affixed within the lumen of the elongate tubular member at the distal end of the elongate tubular member; and a tip for securably affixing the distal portions of the one or more splines; wherein the electrode assembly strip is compressingly and thermally bonded to the outer surface of the flexible polymeric tube to define a flexible electrode assembly strip; wherein the flexible electrode assembly strip is disposed over at least one of the one or more splines; wherein the flexible polymeric tube comprises a polyether block amide material; wherein the electrode assembly strip is compressed into the tubular wall of the flexible polymeric tube to provide a substantially smooth and atraumatic overall outer surface for the flexible electrode assembly strip; wherein substantial portions of the substantially flat electrodes remain substantially flat to provide substantially flat exposed electrodes; and wherein the electrode assembly strip has a thickness from 0.0005 inches to about 0.008 inches.