I love this product! I regularly get kidney stones. Doctors have told me that I need to drink more however I never seem to be able to do it! Fortunately, I find that using this cup seems to get me drinking! I love it so much that I bought a second one so I will always have a clean one! I recommend this product! I drink seltzer constantly and sometimes cups will leak. This has never leaked. I love that you can carry it with one finger too if you have your hands full!