Colder. Hotter. Longer. Happier. Hydro Flask TempShield™ double wall insulation protects temperature from outside
elements. Cold stays icy cold up to 24 hours. Hot stays steaming hot up
to 6 hours. Our customers give these great reviews- one customer claims to have left his in his hot truck all day and still had ice when he got back to it. Can't beat that. The 21 oz Standard Mouth is one of our best selling vacuum insulated water bottles because of it's size and versatility.