Developed for truck applications. Reversible design for installation flexibility. Previously part number know as 19131346. This muffler is considered a "Touring" muffler when compared to the 400130 and used on the same application. Notched necks for 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.