ATI 918582 Super Damper Harmonic Crank Pulley for SR20DET. This truely balanced crank pulley was made to eliminate torsional crankshaft vibrations caused by abnormal wear. It is a direct replacement for the OEM crank pulley. Made to exceed SFI 18.1 Specs with laser engraved timing marks. The ATI Super Damper is also coated with black zinc chromate to prevent rust and reduce wear. The Super Damper does not retain stock belt size. You will need to measure for the correct belt size. Approximate weight of the pulley itself is about 5.7 lbs.