Bests & Worsts Reviews from Amazon

I liked the sports cap for about the first two weeks of having it and before I knew it I was having the same problem with the cap as everyone else. The small rubber piece covering the vent area (very small and can barley even be spotted in pictures ) came off. It is extremely difficult to put back on and I actually was not able to get it back into place (you may not even find the rubber piece after it comes off due to its size. Also because of the complex cap design/length of cap you can't easily put the rubber piece back into place).I stopped using it within two weeks due to this. Once the rubber piece comes off you can no longer effectively use the cap because as soon as you tilt the bottle for a drink or put it in your backpack side ways/titled, water begins to pour out through the small vent. I unfortunaltey didn't read the reviews when I purchased this cap, but I'm hoping my review will help those thinking about purchasing it themselves. You may get lucky and the rubber piece won't come off, but I honestly wouldn't take the risk. As it has happened to many others, including myself. Had the rubber piece stayed intact the sports cap would've been of great convenience.