THE BEST BOTTLE: A 40 oz Wide Mouth water bottle with Hydro Flask's leakproof Flex Straw Cap—easy to fill, easy to drink. Open it up, add your ice, and flip to sip. The insulated stainless steel keeps it cold for up to 24 hours. 24 HOURS COLD: Double-wall vacuum insulation keeps drinks hot or cold for hours. The insulated water bottle keeps beverages cold for 24 hours. The TempShield insulation keeps drinks cold all day. LEAKPROOF: Say goodbye to leaky water bottles. The Flex Straw Cap is leakproof when closed. Simply close it shut and toss it into your bag without worry. Sip effortlessly with one hand, thanks to the easy-to-use straw design. Click it shut, and rest easy knowing your drink stays securely sealed all day. 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