HP-Series Evo7 Evo8 Evo9 4G63 Equal Length Turbo Manifold 11 Gauge / 3.1mm Wall Thickness application: Evolution 4g63t motor - 304 stainless steel - Raw finishing / non polished - Equal length runners design for maximum flow - 3.1 mm wall thickness ( will not crack like the cheap ones out there ) - TIG brass style welded cnc machine flange for resistance against cracking & wearing - Life time warranty - fit TD05 /T517T / T518Z