A polyolefin composition comprising (percent by weight): A) from 65% to 75% of a propylene homopolymer or a propylene copolymer containing from 0.1% to 5.0% of ethylene derived units having a fraction soluble in Xylene at 25° C. lower than 3 wt %; B) from 25% to 35% of an ethylene copolymer containing from 3% to 12% of propylene derived units; said composition having a melt flow rate (MFR) determined according to ISO method 1133 (230° C. and 2.16 kg) comprised between 11 g/10 min and 50 g/10 min; the xylene soluble fraction ranging from 3% to 15% and the intrinsic viscosity (IV) of the xylene soluble fraction ranging from 0.8 dl/g to 2 dl/g.