How Do the kennels attach and are they removable?

Our kennels attach to the back of the run by slotting down on to a couple of 16mm steel pins – we match drill a couple of corresponding holes in the under strut of the kennel and the pins slot into those holes locking the run securely in place.
Yes the kennels are easily removed. In fact if you are heading away for the weekend with the pooch simply whip the kennel off the back of the run, chuck it on the back of your truck and you have the dogs weekend accommodation sorted!