F1 Racing Chromoly Flywheel 51021TFX-HT Ultra heavy-duty and weighs only 15 lbs (stock flywheel weighs 22 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 Works with every clutch including Exedy, ACT, Fidanza, Clutchmasters, and other direct replacement clutch kits