To help reduce excessive exhaust movement that can lead to the occasional rattle or rubbing, we offer highly durable Urethane exhaust hangers which are an exact replacement for the factory units. The urethane mounts are much more rigid than the soft, factory rubber mounts and come in handy when your exhaust system occasionally taps the differential or sway bar during aggressive driving. (STi utilizes 4 exhaust hangers), Each sold separately. Size 15mm