Manifold-Back Dual Exhaust Kit1973-1987 Chevy/GMC 1/2, 3/4, 1-Ton Truck 4WD1973-1987 Chevy Suburban 4WDDoes Not Fit Crew Cab Models350-400 ci Small Block ChevyDiameter: 2.250 in.Aluminized Steel JEGS 555-89003 Manifold-Back Dual Exhaust Kit Features: Includes installation hardware Does Not Include Mufflers Emissions Note:This part is only legal for sale and use on Uncontrolled (Non-Emissions Controlled) Vehicles or on vehicles used solely for the purposes of closed competition racing.CLICK THIS LINK FOR IMPORTANT CARB & EPA EMISSIONS INFORMATION ABOUT THIS PART