The invention relates to a composition comprising a heterophasic propylene copolymer and a C10-C30 aliphatic carboxylic acid amide, wherein the heterophasic propylene copolymer consists of a propylene-based matrix consisting of a propylene homopolymer and/or a propylene-α-olefin copolymer consisting of at least 70 wt % of propylene and at most 30 wt % of α-olefin and wherein the propylene-based matrix is present in an amount of 76 to 90 wt % based on the total heterophasic propylene copolymer and a dispersed ethylene-α-olefin copolymer, wherein the dispersed ethylene-α-olefin copolymer is present in an amount of 24 to 10 wt % based on the total heterophasic propylene copolymer and wherein the sum of the total amount of propylene-based matrix and total amount of the dispersed ethylene-α-olefin copolymer in the heterophasic propylene copolymer is 100 wt %, wherein the amount of ethylene in the ethylene-α-olefin copolymer is 30 to 38 wt %.