High Temperature Noble Metal Thermocouples. Elements are provided to match the ITS 1990 curve. 24 ga. (0.020″) wire is standard – other gauges are available. Insulators are made of Alumina, Mullite, or Hafnia ceramics. Termination can be Bare Strip, Color Coded Sleeving, Fishspine insulators, Copper Sleeves. Porcelain Collar installed for Vertical Applications.