Description Peterbilt Exhaust Tube Replaces OEM: M74-1020-002. Identical replacement part for factory part (OEM: M74-1020-002). It is manufactured in the USA from high-quality 304 Stainless Steel. Tube inlet size: 4″ FLARE Tube outlet size: 4″ FLANGE Hose beaded: No Fitting sizes: None Base tube dia. 4″ Material: 304 stainless steel