Embodiments in accordance with the present disclosure are directed to sensor apparatuses utilizing a one-piece thermal isolated fitting (TIF) tube and methods of assembling the same. In a particular embodiment, a sensor apparatus includes a one-piece thermal isolated fitting (TIF) tube that includes a cylindrical shaped body portion and a flange at one end of the TIF tube. In this example embodiment, the flange has a top surface that is facing away from the cylindrical shaped body portion and an underside surface that is facing towards the cylindrical shaped body portion.