A polyolefin composition comprising: T1) 70-95wt%, of a polyolefin component containing: a1) from 30 wt% to 70 wt% of a propylene based polymer having a propylene content higher than 60 wt% a2) from 30 wt% to 70 wt% of an ethylene based polymer having an ethylene content higher than 70; the sum of the amount of a1) and a2), being referred to the total weight of a1) and a2), being 100; T2) 5-30 wt% of a polyolefin component containing: A) 5-35% by weight of a propylene homopolymer or a propylene ethylene copolymer containing 90% by weight or more of propylene units; component A) containing 10% by weight or less of a fraction soluble in xylene at 25°C (XS A), both the amount of propylene units and of the fraction XS A being referred to the weight of A); B) 20-50% by weight; of a copolymer of ethylene and a C 3 -C 8 alpha-olefin containing from 0.1% to 20% by weight of alpha-olefin units and containing 25% by weight or less; of a fraction soluble in xylene at 25°C (XS B), both the amount of alpha-olefin units and of the fraction XS B being referred to the weight of; and C) 30-60% by weight of a copolymer of ethylene and propylene containing from 25% to 75% by weight of ethylene units and containing from 40% to 95% by weight of a fraction soluble in xylene at 25°C (XSc), both the amount of ethylene units and of the fraction XSc being referred to the weight of; the sum of the amounts of, and being referred to the total weight of, and, being 100; the sum of the amount of T1) and T2), being referred to the total weight of T1) and T2), being 100. T1) 70-95wt%, of a polyolefin component containing: a1) from 30 wt% to 70 wt% of a propylene based polymer having a propylene content higher than 60 wt% a2) from 30 wt% to 70 wt% of an ethylene based polymer having an ethylene content higher than 70; the sum of the amount of a1) and a2), being referred to the total weight of a1) and a2), being 100; a1) from 30 wt% to 70 wt% of a propylene based polymer having a propylene content higher than 60 wt% a2) from 30 wt% to 70 wt% of an ethylene based polymer having an ethylene content higher than 70; T2) 5-30 wt% of a polyolefin component containing: A) 5-35% by weight of a propylene homopolymer or a propylene ethylene copolymer containing 90% by weight or more of propylene units; component A) containing 10% by weight or less of a fraction soluble in xylene at 25°C (XS A), both the amount of propylene units and of the fraction XS A being referred to the weight of A); B) 20-50% by weight; of a copolymer of ethylene and a C 3 -C 8 alpha-olefin containing from 0.1% to 20% by weight of alpha-olefin units and containing 25% by weight or less; of a fraction soluble in xylene at 25°C (XS B), both the amount of alpha-olefin units and of the fraction XS B being referred to the weight of; and C) 30-60% by weight of a copolymer of ethylene and propylene containing from 25% to 75% by weight of ethylene units and containing from 40% to 95% by weight of a fraction soluble in xylene at 25°C (XSc), both the amount of ethylene units and of the fraction XSc being referred to the weight of; A) 5-35% by weight of a propylene homopolymer or a propylene ethylene copolymer containing 90% by weight or more of propylene units; component A) containing 10% by weight or less of a fraction soluble in xylene at 25°C (XS A), both the amount of propylene units and of the fraction XS A being referred to the weight of A); B) 20-50% by weight; of a copolymer of ethylene and a C 3 -C 8 alpha-olefin containing from 0.1% to 20% by weight of alpha-olefin units and containing 25% by weight or less; of a fraction soluble in xylene at 25°C (XS B), both the amount of alpha-olefin units and of the fraction XS B being referred to the weight of; and C) 30-60% by weight of a copolymer of ethylene and propylene containing from 25% to 75% by weight of ethylene units and containing from 40% to 95% by weight of a fraction soluble in xylene at 25°C (XSc), both the amount of ethylene units and of the fraction XSc being referred to the weight of; the sum of the amounts of, and being referred to the total weight of, and, being 100; the sum of the amount of T1) and T2), being referred to the total weight of T1) and T2), being 100.