A polypropylene composition comprising a copolymer of propylene and comonomer units selected from ethylene and alpha-olefins having from 4 to 12 carbon atoms with a total amount of comonomer units of from 10.0 to 16.0 wt%, based on the total amount of monomer units in the polypropylene composition, determined by quantitative NMR spectroscopy, and an alpha-nucleating agent; wherein the polypropylene composition has a xylene cold soluble fraction in a total amount of from 25.0 to 50.0 wt%, based on the total weight amount of the polypropylene composition, determined according to the ISO16152 (first edition; 2005-07-01), with an amount of comonomer units of at least 23.0 wt%, such as 23.0 to 35.0 wt%, based on the total amount of monomer units in the xylene cold soluble fraction, determined by quantitative NMR spectroscopy, a melt flow rate MFR 2 of from 0.5 to 5.0 g/10 min, preferably from 0.8 to 4.5 g/10 min, still more preferably from 1.0 to 4.3 g/10 min and most preferably from 1.2 to 4.0 g/10 min, determined according to ISO 1133 at 230°C and 2.16 kg, and a flexural modulus of not more than 470 MPa, such as from 200 to 470 MPa, determined according to ISO 178 method A (3-point bending test) on 80 mm × 10 mm × 4 mm specimens. a copolymer of propylene and comonomer units selected from ethylene and alpha-olefins having from 4 to 12 carbon atoms with a total amount of comonomer units of from 10.0 to 16.0 wt%, based on the total amount of monomer units in the polypropylene composition, determined by quantitative NMR spectroscopy, and an alpha-nucleating agent; wherein the polypropylene composition has a xylene cold soluble fraction in a total amount of from 25.0 to 50.0 wt%, based on the total weight amount of the polypropylene composition, determined according to the ISO16152 (first edition; 2005-07-01), with an amount of comonomer units of at least 23.0 wt%, such as 23.0 to 35.0 wt%, based on the total amount of monomer units in the xylene cold soluble fraction, determined by quantitative NMR spectroscopy, a melt flow rate MFR 2 of from 0.5 to 5.0 g/10 min, preferably from 0.8 to 4.5 g/10 min, still more preferably from 1.0 to 4.3 g/10 min and most preferably from 1.2 to 4.0 g/10 min, determined according to ISO 1133 at 230°C and 2.16 kg, and a flexural modulus of not more than 470 MPa, such as from 200 to 470 MPa, determined according to ISO 178 method A (3-point bending test) on 80 mm × 10 mm × 4 mm specimens. wherein the polypropylene composition has a xylene cold soluble fraction in a total amount of from 25.0 to 50.0 wt%, based on the total weight amount of the polypropylene composition, determined according to the ISO16152 (first edition; 2005-07-01), with an amount of comonomer units of at least 23.0 wt%, such as 23.0 to 35.0 wt%, based on the total amount of monomer units in the xylene cold soluble fraction, determined by quantitative NMR spectroscopy, a melt flow rate MFR 2 of from 0.5 to 5.0 g/10 min, preferably from 0.8 to 4.5 g/10 min, still more preferably from 1.0 to 4.3 g/10 min and most preferably from 1.2 to 4.0 g/10 min, determined according to ISO 1133 at 230°C and 2.16 kg, and a flexural modulus of not more than 470 MPa, such as from 200 to 470 MPa, determined according to ISO 178 method A (3-point bending test) on 80 mm × 10 mm × 4 mm specimens.