Eureka, end caps DO come off.
As others have mentioned, the description is misleading, as the end caps do not screw off.<br /><br />However, after some fiddling, I was able to get an end cap off to drain the excess water that had been trapped.<br /><br />I have large and fairly strong hands. Even with that, I was not able to get an end cap off.<br /><br />So I used a pair of pliers (channel locks) on and end cap. I held the main tube in the other hand. It was then fairly easy to twist the end cap to remove. A simple push got the cap back on.<br /><br />I'd give a five-star review, as the trap works well, but I've marked it down for the misleading description.
Rating: 3 stars