Love this cap! I initially bought it because my partner only has one working hand so this looked like a promising product that would make using a water bottle easy for him and so it did! Super easy to use and 100% secure, just get used to remembering to close it right after drinking. I spilt some water a couple of times in the beginning but it's not that big of a deal. Otherwise, super secure and joy to drink from. Water flow is much more comfortable than from the original, the black straw-like lid as that takes more effort. This is kind of like drinking without a lid but way more comfortable, you are less likely to spill it on yourself while drinking and you don't need to take the lid off and on every time you drink. Highly recommend it!