Edelbrock triple chrome-plated round air cleaner #1221 work with all popular 5-1/8" diameter carburetors (Performer Series, Thunder Series AVS, Holley, Thermo-Quad, Quadra jet and Carter AFB). The 10" and 14" models have knock-outs in the air cleaner base for use with Edelbrock crank case ventilation adapter #1205 (sold separately). #1208, #1209 and #1221 fit all Edelbrock carburetors. Heights of air cleaners are in parentheses, measured from the gasket flange to the top of the supplied retaining nut. Dimensions are accurate within 1/8".