The present disclosure provides a polyolefin composition made from or containing: A) from about 63 to about 78% by weight of a copolymer of butene-1 with ethylene having a copolymerized ethylene content of up to about 18% by mole and no melting peak detectable at the DSC at the second heating scan; B) from about 22 to about 37% by weight of (i) a propylene homopolymer, or (ii) a propylene copolymer, or (iii) a mixture of two or more of (i) and (ii), having a melting temperature Tm, measured by DSC at the second heating scan, of from about 130° C. to about 165° C.; wherein (i) the amounts of A) and B) are referred to the total weight of A)+B) and (ii) having a melting enthalpy ΔHfus, measured by DSC at the second heating scan, of from 7 to 30 J/g.