Fitting a safe tire chock just got a lot easier. Once you get the right setup, it's very easy to install and uninstall. I had to use the lowest settings to install it because I have a Flagstaff 21FBRS. So if you look at the picture you can see how close the tires are. They advertise that the lock can be used in three different places, I was only able to use it at the end and not the middle as there were no holes. I also found that the standard lock does not fit in the hole due to the diameter of the hole. I fixed it by making the hole bigger.