I ordered what has been a fairy hard to find fit for my old school Airstream that has the curled coupler. Admittedly, the first few times I tried locking it it was hard to get the hang of it, but after a few tries I got it to lock and unlock pretty effortlessly. When locked the lock doesn’t move too much at all but it definitely does not fall off. It works as designed and I’m pretty happy with it. It has a very robust look and feel that will likely make any would be thieves move along to another target. Nice product and at a decent price. Thanks for making locks for the curled coupler. Most manufacturers don’t wanna bother. Glad you guys did!