APEXi N1 Catback Exhaust 2001-2005 Lexus IS300The N1 series muffler has become a staple of the import tuning industry. The N1 was the first of its kind to incorporate the classic angled muffler design that has became so familiar with today's street cars. Born from our involvement in the grueling N1 endurance series, the N1 exhaust system pairs a straight through design racing muffler with free flowing, mandrel bent piping (60. 5mm N A, 80mm for turbo applications). The combination has resulted in