Thermos Vacuum Insulated 18-Ounce Stainless-Steel Hydration Bottle 18-ounce hydration bottle with durable stainless steel interior and exterior Flip-top lid with built-in sipping design; button activated lid and additional clasp for secure travel TherMax double wall vacuum insulation locks in temperature to preserve flavor and freshness Condensation-free with cold beverages--won't leave rings behind Hand wash only