pieces 32 and 34 further contain in the medial portion an insulator block region generally designated by numeral 39 insulator region 39 houses each connector pin so that the union between male connector pin 40 and female connector pin 42 is suitably insulated from any outside chemical or electrical agent in order to withstand the corrosive chemicals and enormous external pressure the outer surface of heater unit connector 30 must be incredibly strong the aforementioned elements of connector 30 are encased in a steel fitting assembly 50 u201c encasement means u201d each component of which is welded with continuous beads using the u201c teg u201d welding process to each adjoining component in the preferred embodiment the outer surface of connector 30 is comprised of stainless steel which is joined using the process of u201c teg u201d welding this welding process allows the seams of joined components to withstand the extreme conditions of the bore well finally each connector piece is secured to the other by fitting assembly 60 fitting assembly 60 and sealing fitting 62 are as would be apparent to anyone skilled in the art designed to engage one another so as to form a sealed junction in the preferred embodiment this union is a standard two inch union that is modified by u201c teg u201d welding that is the union is welded using the teg process so that it will withstand the extreme environmental conditions of the bore well the shielding of the electrical connections between surface wiring leads 24 and heater wiring leads.