Stillen\'s exhaust is 100% stainless steel & features a lifetime warrantee. It makes the most power of any 350Z system on the market and fits like a glove. Tested to add 13 HP at 5600 rpm and 14 Ft/Lbs of torque at 4600 rpm. This is the first and arguably the best full cat back system available for the 350Z. The power and mellow tone have to be experienced to be fully appreciated.Please note this exhaust comes in 2 large boxes so shipping is mildly expensive compared to some other exhausts.