A thermocouple assembly for use in a high-temperature gas path, the assembly comprising: a thermocouple that includes: a first conductor and a second conductor the first and second conductors (202, 204) formed of different materials and coupled to one another by junction; a metal sheath surrounding the first and second conductors (202, 204) wherein the metal sheath is substantially coaxial with both the first conductor and the second conductor; a first termination electrically coupled to the first conductor; a second termination electrically coupled to the second conductor; a first connector configured to couple to the first termination; a second connector configured to couple to the second termination; a housing configured to cover the first and second terminations (304, 306) and the first and second connectors, wherein the housing includes an outer metal portion and an insert molded inner region within the outer metal portion, wherein the insert molded inner region is formed of a glass-mica composite material and is sized and arranged to receive the first and second connectors; and a mounting flange, the mounting flange surrounding the first and second terminations (304, 306) and configured to be fastened to the housing, wherein an insulator surrounds the first and second terminations (304, 306) and insulates the first and second terminations (304, 306) from the mounting flange, and the first and second connectors are insulated from the mounting flange by an insulator. a thermocouple that includes: a first conductor and a second conductor the first and second conductors (202, 204) formed of different materials and coupled to one another by junction; a metal sheath surrounding the first and second conductors (202, 204) wherein the metal sheath is substantially coaxial with both the first conductor and the second conductor; a first conductor and a second conductor the first and second conductors (202, 204) formed of different materials and coupled to one another by junction; a metal sheath surrounding the first and second conductors (202, 204) wherein the metal sheath is substantially coaxial with both the first conductor and the second conductor; a first termination electrically coupled to the first conductor; a second termination electrically coupled to the second conductor; a first connector configured to couple to the first termination; a second connector configured to couple to the second termination; a housing configured to cover the first and second terminations (304, 306) and the first and second connectors, wherein the housing includes an outer metal portion and an insert molded inner region within the outer metal portion, wherein the insert molded inner region is formed of a glass-mica composite material and is sized and arranged to receive the first and second connectors; and a mounting flange, the mounting flange surrounding the first and second terminations (304, 306) and configured to be fastened to the housing, wherein an insulator surrounds the first and second terminations (304, 306) and insulates the first and second terminations (304, 306) from the mounting flange, and the first and second connectors are insulated from the mounting flange by an insulator.