Dow Corning® 702 Diffusion Pump Fluid is a general-purpose fluid designed for fast pumping of large volumes of gas. It is used to produce vacuums in the range of 10-5 to 10-7 torr. It is also used in vapour ejector pumps that attain vacuums of 10-4 to 10-5 torr. DC 702 Diffusion Pump Oil is silicone based fluid with quick pumpdown cycles. It has thermal stability and is resistant to oxidation. Superior vapour pressure capabilities.