As its name implies, Hollywood's F4 Heavy Duty is made from beefy steel tubing that gives it the strength to easily carry 4 bikes. Plus, Hollywood's exclusive dual-position trunk/bumper system allows a custom fit on all sedans, hatchbacks, mini-vans, and SUVs. Sturdy tie-down buckles and side straps ensure a secure fit for heavy loads, too. And, the F4 Heavy Duty comes completely assembled and it folds flat for easy storage.