THE BEST BOTTLE: The 40 oz insulated Hydro Flask water bottle Wide Mouth with a leakproof Chug Cap. The narrow chug spout provides a convenient, controlled flow to quickly quench your thirst. 24 HOURS COLD: Double-wall vacuum insulation keeps drinks hot or cold for hours. The insulated bottle keeps beverages cold for 24 hours. The TempShield insulation keeps drinks cold all day. LEAKPROOF: Say goodbye to leaky water bottles. The Flex Chug Cap is leakproof when closed. Toss it into your bag without worry. Wide Mouth opening fits ice cubes, and Narrow Chug drinking spout provides for a convenient, controlled sip PURE TASTE: Durable pro-grade stainless steel ensures pure taste and no leftover flavor transfer. So, today's water won't have any taste of yesterday's iced tea. DISHWASHER SAFE: Easy to use and easy to clean, just dissasemble, and toss the lid and bottles into the dishwasher. Designed to keep bright color, being dishwasher safe means your favorite Hydro Flask is always at-the-ready.