The straight noble metal thermocouple assemblies illustrated on this catalog page are provided with double protection tubes. Outer protection tube choices of ceramic materials, metal alloys, or composite materials offer thermocouple pro tec tion from a variety of high temperature process heating environments. All assemblies are provided with a ceramic inner tube. These assemblies are available with a variety of process mounting fittings and assembly options as listed below. Spe cial con struc tion de signs are also avail able. Note: Welded bushings will be welded at maximum length possible when X and U dimensions are specified as the same length. Actual U dimension will be 1 to 2 inches shorter than specified depending on bushing size.