The 689900 Speedy Dayton Wheel Adapter allows easy mounting of 20” – 22.5” rims, cutting balancing time in half for most applications. This unit works for all models of truck computer wheel balancers. This unit doubles your production of demountable rim balancing. Lightweight and sturdy! Manufactured form heat-treated aluminum. Easy to mount! It mounts straight literally the first time. The Speedy works great on duplex rims (18″ x 22.5″ tires) for steering axles.