Cable for air blow installation method

For the optical cable, the whole according to the present invention is installed in the duct by the air pressure is to provide the tension and the core tensile member disposed in the center of the optical cable; At least three or more loose tube which is arranged to, each comprising at least one optical signal transmission medium, wrapped around a periphery of said central tensile member; And a binder for loose wrapping of the tube maintains the arrangement; To protect the inside from the outside and comprising an outer shell disposed at the outermost of the optical cable, the forward end face of the optical cable in order to reduce the coefficient of friction of the duct as a whole form a smooth polygon edges. Laying pressure, fiber, binder and fiber