An hermetically sealed electrical feedthrough assembly including an elongated inner electrical conductor having first and second ends; a glass body hermetically sealed around one length portion of the inner conductor adjacent to the first end thereof; a metal adapter hermetically sealed around the glass body and adapted for mounting in a wall of a housing; a tubular outer electrical conductor enclosing and coaxial with another length portion of the inner electrical conductor, the outer electrical conductor being separated from the inner electrical conductor by an annular volume and having one end portion electrically connected to the metal adapter and an opposite end portion disposed adjacent to the second end of the inner electrical conductor; and electrical insulation filling the annular volume and electrically isolating the outer electrical conductor from the another length portion of the inner electrical conductor.