A system and method for pulse-width-modulation communications using an adaptive pulse-duration threshold. By introducing nitrogen at a pressure of more than 0. The first andor the second support has a support element which can shift transversely of the application axis. Alternatively, the system may include a mandrel and first and second mandrel electronics systems in different mandrel sections. The composition of the present invention has high melt tension, without deterioration of the mechanical properties of flame retardant polypropylene, and drastically enhanced characteristics of shape maintenance and a flaming drip during burning.