The N1 Evolution Extreme is based on the proven performance basics of the N1 muffler. Optimum exhaust efficiency is achieved through the mid-pipes running parallel between the catalytic converter and rear muffler section. The H-style piping design was opted to equalize the pressure in both exhaust pipes. Our unique modular design allow the mid-pipes to be interchangeable with the factory OEM exhaust system components along with the rear section which is sold separately.PRODUCT FEATURES:– High-level of quality using tig-welded SUS304 stainless steel uniting quiet performance with high-power performance gains – Matched and manufactured for select chassis – Patented Megaphone piping structure to produce excellent torque and throttle response throughout the powerband. This piping design allows for a swirling exhaust gas flow effect that has for years produced proven results – Compatible with the N1-X Evolution Extreme rear section part number 164-KT07