These new gaskets fit 4150 Series 390-450 CFM Holley 4 barrel carbs with vacuum secondary, 1-7/16" throttle bores and removable jets in the secondary. List #'s 1272-A^ , 1272-1A^ , 1273-A^ , 1273-1A^ , 1273-2A^ , 1312-A^ , 1312-1A^ , 1426-A^ , 1616-A^ .