what a POS! I bought 2 packs for my new caravan. They were pretty easy to put on but make sure you don't want to go anywhere as they are almost impossible to take off. In fact, they were impossible to remove. I couldn't press the button deep enough to release them when I finally unlocked one of them. I had to get out my saw and then it took me less than 30 seconds to cut through the cheap square tubing they're made of, allowing a skilled thief to dismount your device and take it in a minute or less if that were yours only security measure. .