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.