I had high expectations for this tumbler seeing as it is vacuum insulated, and it did not disappoint. I use this for storing my baby's (already chilled) milk for daycare. I add some reusable ice cubes, and they are still partially frozen at the end of the day! The flip lid seals tight and makes it easy to pour out of. This has removed the stress from trying to keep plastic bottles cold during transport, and as a bonus, it fits in my car cupholder.