The 21 oz vacuum insulated Hydro Flask is our most versatile medium sized water bottle and one of our most popular. With a convenient 21 oz capacity and a 1.81″ mouth opening great for sports drinks, thicker liquids or nearly any size ice cube, this is a drinking bottle as diverse as you!

The 21 oz insulated bottle is made from 18/8 food-grade stainless steel and the double wall vacuum insulation provides top notch insulation power, keeping cold liquids icy cold for up to 24 hours and hot liquids steaming hot for up to 12 hours.

Hydro Flask is proud that all our products are BPA-free, 100% recyclable and are backed by a lifetime warranty. Look for the H-guy and Hydro Flask logo to ensure youâ??re getting the marketâ??s premium insulating beverage bottle.