The 18oz Standard Flex Cap Flask is constructed from 18/8 pro-grade stainless steel to maximise durability. The stainless-steel construction also ensures a pure taste and no flavour transfer between the flask and your beverage. Meanwhile, the proprietary powder coating helps you keep your grip, keeping the flask sweat free, and adding another layer of durability. Hydro Flask’s unique TempShield™ technology utilises double wall vacuum insulation which protects temperature for hours. It keeps cold drinks icy and hot drinks piping – allowing you to stay refreshed for any adventure.