I put Proline 2.2 All Purpose Truck wheels on my ZX-5. It uses 12mm hexes
so I bought the Traxxas adapters, but had to buy two sets and only use the
two rear adapters from each package. I did have to grind 1mm off the rear of
each adapter because the hex recess was too deep and the adapter rubbed on the buggies hub. This did give me the ground clearance and traction I needed for running on my backyard track. I did gear down for the taller tires.