I have a few sample tubes and so far, I've tested it through tears. It kept my mascara from running although it did clump and my lashes stuck together. I haven't tried it in the pool and in full water or anything....I'm not sure it's somethingid buy. Some ppl say that the mascara they love isn't available in waterproof so it's a great idea. I haven't had to buy new mascara recently, andim not sure if what I like is available in waterproof, so it may be a good tool for me eventually.