With 50 Ohm, 75 Ohm impedance, they are used as distribution cable where low attenuation is required for indoor CATV, CCTV, Cable TV, satellite, Radio and Data telecommunication systems. There are also the types for indoor, outdoor aerial distribution systems, use for underground, armoured types as well as types produced according to military standards. There are types with double or triple screens. Screening provides protection against electrical effects coming from outside. Types produced with HFFR content catch fire in a prolonged period of time during fire and fire mostly dies down in the end. They have low smoke density and they do not emit poisonous and corrosive gasses during a fire. They are used in buildings where there is intense human population.