STREET PERFORMANCE CARBURETOR, 750 CFM -- Four Barrel, Easy Bolt On Installation, Shiny Finish, Vacuum Secondarys, Power Valve Blow-Out Protection, Wet-Flow Tested And Calibrated For Excellent Street Drivability, Vacuum Secondary, Square Flange, Model 4160, Use Adapter Part Number 17-6 When Using A Square Flange Carburetor With A Spread Bore Manifold, Not For Use In California Series: Street Performance