This Powerforce+Plus damper is dimensionally the same as the popular JDM single accessory drive pully that many racers are using, except this is a true harmonic damper. The alternator will run 11% underdrive on B-16, 12% under on a GSR and 7% under on a Type R. No provision for A/C or power steering drive belts with this damper. The damper is made of 1045 steel and meets SFI spec #18-1 for all racing.