ACT flywheels are lighter, stronger and safer than stock cast flywheels to meet the needs of both enthusiast and hard core racer. Material is properly distributed for maximum strength, lower inertia, good heat tolerance and rigidity. Precision machined threads will not easily strip out or get damaged like those found on aluminum flywheels. ACT engineers XACT flywheels using the latest CAD and FEA (finite element analysis) software to evaluate all design alternatives to get the best results possible. By hot forging chrome-moly steel, each flywheel yields an ultra fine centralized grain structure that is superior in strength to any other manufacturing method. ACT gives extra effort to strategically slot XACT ProLite flywheels to lower inertia without sacrificing strength and heat dissipation. All flywheels are CNC machined and dynamically computer balanced for super smooth high RPM reliability. This Flywheel is meant to replace your OEM Subaru flywheel. ProLite Flywheels are recommended for race applications and often can trigger a CEL. If using for Street, look into the StreetLite Flywheel. This ProLite Flywheel is 9.6 LBS.