Are Pelican Turmblers Leak-Proof? They aren't, and here's why:

The Pelican Traveler Tumblers have many superpowers. Including keeping your drinks hot for 12 hours/cold for 24 and being guaranteed for life.

However, if the tumbler is tipped over, you may notice your liquid escaping from the mouthpiece. This is because there isn’t an o-ring around the mouthpiece like there is around the grooves of the lid (see above photo) Enjoy the easy screw-in lid and 18/8 pro-grade stainless steel tumbler, but plan accordingly! If you are in need of truly leak-proof drinkware, then check out the Pelican bottles here. #StayPelicanProud