do not worry, mine were really loose when I got my Zenith's. They are nice and snug now, probably takes a couple weeks for them to snug everything up. I was actually quite annoyed about this when I first got them. They were utterly perfect except for the loose cap, and it was almost a deal breaker for me. Thankfully I decided to give them some time and sure enough, the cap is real snug now, nice click when it goes in place. I did order o-rings though, i think they're 1mm x 17mm, they were back ordered, so I am still waiting for them.