The Thule EasyFold XT Bike Rack # TH903202 does secure itself using the anti-rattle tightened down inside the receiver on your tow vehicle. There is a lock on the knob which prevents the anti-rattle mechanism from being loosened and that is what secures it to your vehicle. The locks on the knobs are the same locking mechanism used to secure your bikes to the bike rack. We have tested the locks in our facility and they are very secure and we have tested the bike rack on your speed bump courses... view full answer...