the present invention is directed to a header assembly attachable to a medical device for the purpose of connecting its output terminals to at least one lead , the lead terminating at a target organ or portion of the body intending to be assisted . a number of leads are connectable to the header , including single and coaxial leads . the header assembly may be molded directly to the medical device or preformed and then attached to the device casing , either by mechanical fastener and / or chemical adhesive .