This OXO soft works travel mug has been my go to tea mug at work for many many years, and it’s still works just as wonderfully as the first day I used it. It keeps my tea nice and warm, and I love how well this mug seals. It is leak proof as long as you have the button on the cap in the closed position. Even with daily use, this mug still looks just as good as the day that I got it. Just like every other product that I have ever purchased from this brand, it’s high-quality.