A catheter sheath for a basket catheter comprising an electrical lead having a proximal end and a distal end and a lumen extending from the proximal end to the distal end. Each electrical lead comprises a tubular member of non-conductive material, a plurality of electrical conductors extending from the proximal end to the distal end and disposed on the non-conductive tubular member, And an outer layer of a nonconductive material covering the conductor covered by the outer layer. The catheter sheath further comprises one or more electrodes at the distal portion of each electrical lead that are in electrical communication with at least one of the plurality of electrical conductors through the outer layer. An elongated shape forming member is received in each lumen of the plurality of electrical leads. The shaping member imparts an arcuate shape to each distal portion of the electrical lead so that the distal portion of the catheter sheath forms a basket shape. The plurality of electrical leads are bundled together at their distal ends and proximally to the distal arches of each electrical lead. (FIG.
