The first letter in the Sullins Connector Solutions part number indicates the material code for insulator and contact. When the insulator and contact materials are used together, the operating temperature is rated at the lower of the two materials. For instance, PA9T material is rated at 150°C, and Phosphor Bronze is rated at 125°C. When coupled together, the overall operating temperature is rated at the lower of the two materials, which is 125°C. Different material combinations also have different processing temperatures.