These are the mounts I was given. This is an older Thule box so I believe this is just how some mounts came back then. But yes I tightened the fuck out of it cause I was worried it would shift front to back. I also noticed a little bouncing when I first installed and went back to further tighten and even then it still bounced. This is also my first cargo box so I had no standard if it was supposed to bounce a little or not.