CMP FT6 PVC WIRE is the highest flame retardant wire which was widely used in air return pressurization systems for ventilation ducts or air handling equipment, For example, in the event of a fire, such cables can limit the spread of flames to 5 feet or less, and can also limit the optical density of smoke released during combustion. This descriptor indicates that cables are suitable for installation in pipelines, pressurized spaces, and spaces with ambient air circulation, such as spaces above elevated floors or suspended ceilings.