A monophasic bimodal propylene/ethylene/1-butene random terpolymer composition (PP) comprising: a) 40 to 90 wt.-%, relative to the total weight of the monophasic bimodal propylene/ethylene/1-butene random terpolymer composition, of a first random terpolymer fraction (PP1), having an ethylene content (C2), as determined by 13 C-NMR spectroscopy, in the range from 0.3 to 3.0 mol-%, and a 1-butene content (C4), as determined by 13 C-NMR spectroscopy, in the range from 1.0 to 5.0 mol-%; and b) 10 to 60 wt.-%, relative to the total weight of the monophasic bimodal propylene/ethylene/1-butene random terpolymer composition, of a second random terpolymer fraction (PP2), having an ethylene content (C2), as determined by 13 C-NMR spectroscopy, in the range from 3.0 to 7.0 mol-%, and a 1-butene content (C4), as determined by 13 C-NMR spectroscopy, in the range from 2.0 to 6.0 mol-%, wherein the first random terpolymer fraction (PP1) and the second random terpolymer fraction (PP2) combined make up at least 95 wt.-% of the total weight of the monophasic bimodal propylene/ethylene/1-butene random terpolymer composition (PP), wherein the monophasic bimodal propylene/ethylene/1-butene random terpolymer composition (PP) has each of the following properties: i) an ethylene content (C2), as determined by 13 C-NMR spectroscopy, in the range from 1.0 to 4.0 mol-%; ii) a 1-butene content (C4), as determined by 13 C-NMR spectroscopy, in the range from 1.5 to 4.5 mol-%; iii) a melt flow rate (MFR 2 ), determined according to ISO 1133 at 230 °C at a load of 2.16 kg, in the range from 3.0 to 10 g/10 min; and iv) a content of 2,1-regiodefects, as determined by quantitative 13 C-NMR spectroscopy analysis, in the range from 0.1 to 1.5 mol%. a) 40 to 90 wt.-%, relative to the total weight of the monophasic bimodal propylene/ethylene/1-butene random terpolymer composition, of a first random terpolymer fraction (PP1), having an ethylene content (C2), as determined by 13 C-NMR spectroscopy, in the range from 0.3 to 3.0 mol-%, and a 1-butene content (C4), as determined by 13 C-NMR spectroscopy, in the range from 1.0 to 5.0 mol-%; and b) 10 to 60 wt.-%, relative to the total weight of the monophasic bimodal propylene/ethylene/1-butene random terpolymer composition, of a second random terpolymer fraction (PP2), having an ethylene content (C2), as determined by 13 C-NMR spectroscopy, in the range from 3.0 to 7.0 mol-%, and a 1-butene content (C4), as determined by 13 C-NMR spectroscopy, in the range from 2.0 to 6.0 mol-%, wherein the first random terpolymer fraction (PP1) and the second random terpolymer fraction (PP2) combined make up at least 95 wt.-% of the total weight of the monophasic bimodal propylene/ethylene/1-butene random terpolymer composition (PP), wherein the monophasic bimodal propylene/ethylene/1-butene random terpolymer composition (PP) has each of the following properties: i) an ethylene content (C2), as determined by 13 C-NMR spectroscopy, in the range from 1.0 to 4.0 mol-%; ii) a 1-butene content (C4), as determined by 13 C-NMR spectroscopy, in the range from 1.5 to 4.5 mol-%; iii) a melt flow rate (MFR 2 ), determined according to ISO 1133 at 230 °C at a load of 2.16 kg, in the range from 3.0 to 10 g/10 min; and iv) a content of 2,1-regiodefects, as determined by quantitative 13 C-NMR spectroscopy analysis, in the range from 0.1 to 1.5 mol%. i) an ethylene content (C2), as determined by 13 C-NMR spectroscopy, in the range from 1.0 to 4.0 mol-%; ii) a 1-butene content (C4), as determined by 13 C-NMR spectroscopy, in the range from 1.5 to 4.5 mol-%; iii) a melt flow rate (MFR 2 ), determined according to ISO 1133 at 230 °C at a load of 2.16 kg, in the range from 3.0 to 10 g/10 min; and iv) a content of 2,1-regiodefects, as determined by quantitative 13 C-NMR spectroscopy analysis, in the range from 0.1 to 1.5 mol%. <EOS>