Flexible cable insulation composition comprises a copolymer of ethylene and 1-octene POE, LLDPE, block copolymer styrene-ethylene-butylene-styrene, calcium carbonate, silicon dioxide, γ-aminopropyltrimethoxysilane, vinyl-trimethoxysilane, di-tert-butyl peroxide, peroxide benzoyl, pentaerythritol tetrakis-[3-[3,5-di-tert-butyl-4-hydroxyphenyl]propionate, tris(2,4-di-tert-butylphenyl)phosphite and tin dibutyl dilaurate