Fluoro rubber – FKM FKM materials have conquered many applications in which high thermal and / or chemical resistance is required. FKM also has excellent resistance to ozone, weathering and ageing. Very low gas permeability, FKM is recommended for vacuum applications. FKM has good resistance to: mineral oil-based oils and greases aliphatic hydrocarbons aromatic hydrocarbons chlorinated hydrocarbons hydraulic fl uids HFD vegetable and animal oils and fats silicone oils and silicone greases fuels non-polar solvents ozone, weathering, ageing, UV resistance FKM is not resistant to: glycol-based brake fl uids polar solvents (e.g., acetone) superheated steam (special grades) hot water (special grades) amines, alkalis (special grades) low-molecular organic acids (e.g., acetic acid) Application temperature range: -15 to +200°C (short term +220°C) down to -61°C and up to 260° C is realistic with special grades