To use this lock is pretty simple, go ahead and flip open the rubber cap and get your key. You can unscrew it this way or you can hold the key and twist the other side and it comes apart. That is all there is to it. Now we will go ahead and show you how it gets installed on to a 1 1/4 inch receiver hitch. Now that we have our hitch here, it is a matter of reversing the procedure. Hold the key and just twist the other half. Now back the key up about a quarter turn, then that is that and it cannot come apart. That is part # 40106, the stainless steel hitch lock for 1 1/4 inch receivers.