Edwards ULTRAGRADE™ Performance 19 uses a solvent refining process, whereas this oil is produced by a unique hydro treating process. This process eliminates nitrogen, sulphur and oxygen and the aromatic hydrocarbons, leaving a clear base stock essentially free of impurities. When combined with additives, the ULTRAGRADE™ Performance oils give improved vacuum performance, thermal and oxidation stability and rust inhibition. The properties of the oils allow them to be used in a wide range of applications. Oil Service Data Sheet Edwards Oil MSDS