(GJFBV)Indoor duplex flat fiber optic cable, use 900um or 600um flame-retardant tight buffer fiber as optical communication medium. the tight buffer fiber wrapped with a layer of aramid yarn as strength member units, such unit is extruded with a layer of PVC or LSZH material as an inner jacket. then the cable is completed with a layer of flat PVC or LSZH jacket as out sheath.