For the love of parks, Hydro Flask is proud to support the National Park Foundation. Our shared mission is to help protect America’s national parks, connect people to nature and inspire the next generation of park stewards. The 2024 collection features Yellowstone, Yosemite and Zion bottles. 24 hours cold. 12 hours hot. TempShield double-wall vacuum insulation Leakproof when closed Pure taste, no flavor transfer Dishwasher safe Easily fits ice cubes Bottle fits most backcountry water filters BPA-Free Not for use on a stove, in a microwave or freezer.