A polymer composition comprising at least one EPDM polymer, wherein the at least one EPDM has an ENB content per polymer chain (EPC) of from 80 to 150 determined according to equation (I): EPC = ( [ ENB ] × 10 × Polymer ⁢ Mn ) / 120 ⁢ g / mol ( I ) wherein ‘[ENB]’ is the content of units derived from ENB in the EPDM polymer in % by weight (based on the total weight of the polymer which is 100% by weight) and Polymer Mn is the number average molecular weight in kg/mol of the EPDM polymer as determined by gel permeation chromatography a content of ENB from 6 to 20% by weight. Also provided is a polymer blend composition comprising a blend of a first EPDM polymer and a second EPDM polymer wherein the polymer blend has an ENB content per polymer chain (EPC) of from 80 to 150 and wherein the polymer blend has a total ENB content of from 7.5 to 20% by weight based on the total weight of the polymer blend. Also provided are curable compounds containing the polymer or the blend, methods of making the compounds, cured compounds and articles.