A fluoroelastomer composition [composition] comprising: - at least one fluoroelastomer [fluoroelastomer] comprising from 0.1 to 10.0 % moles of recurring units derived from at least one cure-site containing monomer having at least a nitrile group [monomer], with respect to total moles of recurring units, and comprising iodine and/or bromine cure sites in an amount such that the I and/or Br content is of from 0.04 to 10.0% wt, with respect to the total weight of fluoroelastomer; - at least an organic peroxide [peroxide]; - at least one bis-olefin [bis-olefin] having general formula: wherein R 1, R 2, R 3, R 4, R 5 and R 6, equal or different from each other, are H or C 1 -C 5 alkyl; Z is a linear or branched C 1 -C 18 (hydro)carbon radical (including alkylene or cycloalkylene radical), optionally containing oxygen atoms, preferably at least partially fluorinated, or a (per)fluoro(poly)oxyalkylene radical comprising one or more catenary ethereal bonds. and - at least one compound [compound] selected from the group consisting of: (A- 1) bis-amino(thio)phenol compounds [aminophenol] of formula: wherein: - A is a bond, -SO 2 -, -O-, -C -, or a (fluoro)alkyl of 1 to 10 carbon atoms (specifically a perfluoroalkyl of 1 to 10 carbon atoms); - each of E, equal of different at each occurrence, is oxygen or sulphur, preferably oxygen, and wherein the amino and -EH groups are interchangeably in ortho, meta or para positions with respect to the group A; and (A-2) aromatic tetraamine compounds [amine] of formula: wherein: - A' is a bond, -SO 2 -, -O-, -C -, (fluoro)alkyl of 1 to 10 carbon atoms (specifically a perfluoroalkyl of 1 to 10 carbon atoms); - each of R N, equal to or different from each other, is a hydrogen atom or a C 1 - C 12 hydrocarbon group, preferably an aryl group; and - the amino groups are interchangeably in ortho, meta or para positions with respect to the group A'. - at least one fluoroelastomer [fluoroelastomer] comprising from 0.1 to 10.0 % moles of recurring units derived from at least one cure-site containing monomer having at least a nitrile group [monomer], with respect to total moles of recurring units, and comprising iodine and/or bromine cure sites in an amount such that the I and/or Br content is of from 0.04 to 10.0% wt, with respect to the total weight of fluoroelastomer; - at least an organic peroxide [peroxide]; - at least one bis-olefin [bis-olefin] having general formula: wherein R 1, R 2, R 3, R 4, R 5 and R 6, equal or different from each other, are H or C 1 -C 5 alkyl; Z is a linear or branched C 1 -C 18 (hydro)carbon radical (including alkylene or cycloalkylene radical), optionally containing oxygen atoms, preferably at least partially fluorinated, or a (per)fluoro(poly)oxyalkylene radical comprising one or more catenary ethereal bonds. and - at least one compound [compound] selected from the group consisting of: (A- 1) bis-amino(thio)phenol compounds [aminophenol] of formula: wherein: - A is a bond, -SO 2 -, -O-, -C -, or a (fluoro)alkyl of 1 to 10 carbon atoms (specifically a perfluoroalkyl of 1 to 10 carbon atoms); - each of E, equal of different at each occurrence, is oxygen or sulphur, preferably oxygen, and wherein the amino and -EH groups are interchangeably in ortho, meta or para positions with respect to the group A; and (A-2) aromatic tetraamine compounds [amine] of formula: wherein: - A' is a bond, -SO 2 -, -O-, -C -, (fluoro)alkyl of 1 to 10 carbon atoms (specifically a perfluoroalkyl of 1 to 10 carbon atoms); - each of R N, equal to or different from each other, is a hydrogen atom or a C 1 - C 12 hydrocarbon group, preferably an aryl group; and - the amino groups are interchangeably in ortho, meta or para positions with respect to the group A'. (A- 1) bis-amino(thio)phenol compounds [aminophenol] of formula: wherein: - A is a bond, -SO 2 -, -O-, -C -, or a (fluoro)alkyl of 1 to 10 carbon atoms (specifically a perfluoroalkyl of 1 to 10 carbon atoms); - each of E, equal of different at each occurrence, is oxygen or sulphur, preferably oxygen, and wherein the amino and -EH groups are interchangeably in ortho, meta or para positions with respect to the group A; and - A is a bond, -SO 2 -, -O-, -C -, or a (fluoro)alkyl of 1 to 10 carbon atoms (specifically a perfluoroalkyl of 1 to 10 carbon atoms); - each of E, equal of different at each occurrence, is oxygen or sulphur, preferably oxygen, and wherein the amino and -EH groups are interchangeably in ortho, meta or para positions with respect to the group A; and (A-2) aromatic tetraamine compounds [amine] of formula: wherein: - A' is a bond, -SO 2 -, -O-, -C -, (fluoro)alkyl of 1 to 10 carbon atoms (specifically a perfluoroalkyl of 1 to 10 carbon atoms); - each of R N, equal to or different from each other, is a hydrogen atom or a C 1 - C 12 hydrocarbon group, preferably an aryl group; and - the amino groups are interchangeably in ortho, meta or para positions with respect to the group A'. - A' is a bond, -SO 2 -, -O-, -C -, (fluoro)alkyl of 1 to 10 carbon atoms (specifically a perfluoroalkyl of 1 to 10 carbon atoms); - each of R N, equal to or different from each other, is a hydrogen atom or a C 1 - C 12 hydrocarbon group, preferably an aryl group; and - the amino groups are interchangeably in ortho, meta or para positions with respect to the group A'.