ADRENALIN R series Muffler systems are manufactured in New Zealand by City Steel and Engineering. Using Sanderson tube louvre technology we are breaking new ground in the production of aftermarket performance exhaust solutions.The R is for:? 100% T304 Aircraft quality stainless steel? Patented spiral lourve duct technology? 3 stage sound absorption medium? Proven performance gains with deeper tone? Suitable for highly tuned race & street cars? Mirror polished embossed casingl? Available in custom sizesSanpro Industries were awarded the prestigious Design Mark for their patented Turboflow muffler design. It is this combination of expertise making the ADRENALIN R series the hardest performing muffler available today with proven success in the automotive racing and performance tuning industry.