Krytox, a registered trademark of The Chemours Company, is a group of colorless synthetic lubricants (oils and greases) with a variety of applications. Invented by researchers at DuPont, Krytox oils are fluorocarbon ether polymers of hexafluoropropylene oxide, with a chemical formula: F−(CF(CF3)−CF2−O)n−CF2CF3, where the degree of polymerization, n, generally lies within the range of 10 to 60. These compounds are collectively known by many names including perfluoropolyether (PFPE), perfluoroalkylether (PFAE), and perfluoropolyalkylether (PFPAE). A unique identifier is their CAS registry number, 60164-51-4.