I don’t know how it stays sturdy being curved and only tension, but this rod is awesome. I put it up by myself and expected it to come crashing down. Best part is that you don’t have to drill and attach somewhat permanently. I still haven’t learned to measure twice, so the ability to put it up see how I like it and then move it, which I have done several times, was important. So far it has stayed up, even with the kitty trying to pull the curtain off while I shower!