Apiezon M is widely used as a high vacuum grease due to its low vapor pressure and excellent thermal stability. It provides reliable sealing and lubrication in vacuum systems operating under extreme conditions, such as in mass spectrometers, vacuum ovens, and diffusion pumps. Its resistance to oxidation and minimal outgassing make it ideal for maintaining vacuum integrity over long periods. It is also used in cryogenic applications and in the maintenance of laboratory glassware joints where a secure, long-lasting seal is required. Apiezon M performs well in environments with limited exposure to air and is preferred in applications where silicone-based greases might degrade or contaminate the system.