Small Block Ford, 157-Tooth, 24.5 lb, 28 oz External Balance. Hays flywheels are certified under SFI spec 1.1.
12-535 Hays Billet Steel SFI Certified Flywheel - Small Block Ford
10-140 Hays Billet Steel SFI Certified Flywheel - Small Block Chevrolet
10-130 Hays Billet Steel SFI Certified Flywheel - Small and Big Block Chevrolet
12-242 Hays Billet Steel SFI Certified Flywheel - Ford FE