This 2-into-1 exhaust system fits all 1971 thru 1984 FX models with Shovelhead engines. The unique 4" disc system at the end of the exhaust gives you the opportunity to wave-tune your Shovelhead engine to get maximum Horsepower. Each system comes with a special mounting bracket and heat shield for the rear pipe. Can also be used on kick start equipped motors, if the late-style fold-out kick arm (ZPN290313) is used, or if the kick starter shaft is replaced by an extra long shaft (ZPN235845). Available in chrome or polished finish.