Dual inlet and dual outlet. Internal X-Pipe for increased performance and improved sound. Notched necks for easy clamp-on installation. Reversible design for installation flexibility. High-quality T-304 Stainless steel will never rust. 100% welded construction for strength. Free Flow design for improved performance. High-temperature continuous-filament fiber (CFF) acoustic material for sound control. Natural mill finish can be brushed or polished prior to installation.