Aluminum clamp on velocity stacks for Iron Barrel models running the OEM quality Mikuni carburetor. Available for 350cc and 500cc models. A period correct look for any carbureted Royal Enfield. They are the clamp-on style so they can be fitted to any carb with the correct OD flange measurement.
The 350cc version measures 43mm ID
The 500cc version measures 44mm ID
Will require upjetting the carburetor to compensate for the increase in air flow.