Now I know why other brands are more money for the same design. The rails do not sit flush with the factory rails. There are these stupid tabs they give you to shim the rails but this made it worse. The center of the rails kept bowing in causing the cover bars to not fit in the channel. I even used extra clamps to try and stop this from happening. Also don't over tighten the clamps as the cheap aluminum bends easily. Once again, I'm not impressed. I have had better luck with cheaper covers.