I chose this for my 7x14 trailer so I can lock it down when taking it off the truck. I just needed something to stop it from rolling. So far I've used them on cobblestones, grass and concrete and haven't had any problems. Well to be honest; I live in Florida and it's "flat country" so I haven't tested them with any significant bias. However, the incline was enough to get the trailer to roll on its own, allowing it to do its job. Overall I am very satisfied because it does what I need. Seems strong enough that I can't easily break it. I'll let you know when I do.