It is an adorable tumbler and is a great size, but it leaks! I filled it about 3/4 of the way, and it spilled out the top. The lid doesn't screw on very well - it is one of those that if you screw it on too tightly, it comes loose...if that makes sense. Regardless, it spilled all over my car and pants the first few times I used it. I'm about to give up and use it as a pencil holder for my desk because it is too cute to give up. That being said, it does keep liquids warm.