F1 Racing Lightweight Chromoly Flywheel 52020FX-HT Ultra heavy-duty and weighs only 13 lbs Meets or exceeds SFI 1.1 specification Made from 4140 forged chromoly steel (2X stronger than billet steel) Incorporates special design features to enhance the airflow for improved clutch cooling Work with any clutch including Exedy, ACT, Fidanza, Clutchmasters, etc