Title: Great Mug -does not leak -
Review: This is a terrific mug. I've got a couple of the older flip-seal Contigo mugs - one is the carabiner, that don't leak --except when I forget to close the flip-seal. (I've done this too many times to admit. )This Contigo insulated tumbler is better still -- it's idiot proof. I bought two, they don't leak, won't leak and I couldn't make them leak. These are as secure as a screw top thermos.I've taken them up to 10,000 feet and they didn't leak.Re: The cleaning problem some people are having. I put coffee in my mugs so this may not apply to other substances.Every now and then I'll soak them in vinegar solution 50/50 for a few hours. That seems to clean up staining & build up.
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