591 ml. Colder. Hotter. Longer. Happier. Keeps your drink at the perfect temperature so you can stay refreshed for any adventure. BPA free. 18/8 pro-grade stainless steel. Lifetime warranty. TempShield: Our unique double wall insulation. Our unique double wall insulation protects temperature for hours. Easy grip. Sweat free. Built to last. HydroFlask.com. Designed in Bend, OR. Made in China.