The ARC 6611-HIV Adjustable Steel Hub fits the crankshaft taper of the Briggs Model 40, Model 44 and Model 49 Intek V-Twins. 

The ARC 6611 Series Flywheels are a modular series of flywheels that allow you to change engine platforms by changing out the inner hub, ring gear, and coil hardware if needed. In other words, if you want to use your Intek Single or Vanguard V-Twin ARC 6611 Flywheel on your Intek V-Twin, rather than buying a brand new flywheel, buy this hub, Intek V-Twin ring gear, and coil hardware to convert it.