The Guardian is crafted from rotationally-molded, high-impact polyethylene to absorb the impact of rocks, gravel and road debris Q instead of ricocheting it back at the motorhome. The Guardian can be attached and removed in seconds, and fits all ROADMASTER tow bars equipped with quick-disconnects. Can also be used with a tow dolly to help protect your towed vehicle by using a Guardian bracket (part number 2000-8). If you tow more than one vehicle, the Second Vehicle Kit has all the mounting hardware necessary to swap the Guardian from one vehicle to another.