Notched necks for easy clamp - on installation. Compact size is perfect for applications with limited space. Reversible design for installation flexibility. High - quality T - 304 austenitic 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.