Perfluoroelastomer (FFKM) O-Rings

Kalrez FFKM O-Rings

From aerospace and chemical processing to chip manufacturing and oil and gas applications, DuPont™ Kalrez® elastomers are engineered to provide more stability, more resistance, and more effective sealing.

Perfluoroelastomer (FFKM) currently offers the highest operating temperature range, the most comprehensive chemical compatibility, and the lowest off-gassing and extractable levels of any rubber material.

FFKM materials are perfluoroelastomeric compounds containing an even higher amount of fluorine than FKM fluoroelastomers.


They have improved resistance to high temperatures and chemicals and even withstand environments where Oxygen-Plasma are present for many hours. Certain grades have a maximum continuous service temperature of 327 °C (621 °F). They are commonly used to make O-rings and gaskets that are used in applications that involve contact with hydrocarbons or highly corrosive fluids, or when a wide range of temperatures is encountered.

O-ring applications can be very demanding.  GFS Engineers are available to consult on any O-ring application.  Click here to contact a GFS Engineer.


Kalrez 4079

Kalrez 4079 is a black, low compression set product that has excellent chemical resistance, good mechanical properties and outstanding thermal stability. Kalrez® 4079. A maximum continuous service temperature of 316 °C is suggested. Short excursions to higher temperatures are also possible.

Kalrez 6375

Kalrez® 6375 is designed to give outstanding performance in the widest possible range of chemicals and temperatures. This product is an excellent choice for use in acids, bases, amines, steam, ethylene oxide, and many other aggressive chemicals. Mixed streams, once a problem for many chemical processors, can now be handled by 6375.