PETROTEMP HT is a synthetic polymer designed for high temperature drilling environments. It is compatible with all commonly used materials in water-based drilling fluids and is used for high temperature fluid loss control and inhibition of cutting and shales. In typical fresh and saltwater muds, PETROTEMP HT perfoms well up to 375 °F in lab testing and has shown excellent performance in formate fluids above 400 °F. In field muds, thermal stability might be expected to be higher.