Easily attaches to exisiting tow ball mount Rubber padding surrounds the bike clamps to hold the bike securely and protect the finish Holds a variety of bike sizes including road, mountain and fat tire bikes with frames up to 2 1/2″ Secure your rack to the vehicle using the SportRack Hitch Bike Rack Locking Knob (sold separately) Holds up to 2 bikes Max weight of 90 lbs/40 kg