FKM is the ASTM designation for a class of fluorinated, carbon-based synthetic rubber, commonly known as fluoroelastomer. FKM (commonly referred to as FKM rubber) has impressive heat resistance, allowing FKM seals to withstand temperatures greater than 200°C. FKMs also exhibit extraordinary levels of resistance to high pressures, chemicals, and other fluids (including several fuels).

FKM is commonly used to manufacture o-rings, seals, and gaskets. FKM seals and FKM o-rings are used in a variety of high-performance applications in the automotive, aerospace, energy, industrial, and semiconductor industries.


Greene, Tweed manufactures FKM sealing solutions for a variety of applications in a range of industries.  View each compound's benefits, temperature range, primary applications, and more.

The Greene Tweed Fusionfamily of FKM-based elastomers are engineered to deliver superior sealing performance than standard FKM materials in challenging operating environments.

Fusion™ elastomers have been engineered to withstand conditions such as rapid gas decompression (RGD), low and high temperatures, and to ensure minimal particulation in clean environments.

The Fusionproduct line combines Greene Tweed’s engineering, design, and materials expertise, focus on continuous product improvement and high-touch customer support and collaboration to develop highly engineered solutions that meet the rapidly evolving needs of the diverse markets we serve.