Lets start with Hydro Flask's new Flex Sip! The Flex Sip is leakproof, compatible with any other wide mouth flask and, as the name implies, can be sipped while on the go; a brilliant upgrade to an already brilliant little flask. Hydro Flask uses TempShield, a double wall,vacuuminsulated technology that guards the temperature of any drink, meaning coldstays cold for up to 24 hours and hot stays steaming hot for up to 12 hours. TempShield also guarantees no condensation or heat transfer to the outside of the bottle. All of Hydro Flasks products are made with 18/8 pro-grade stainless steel which works wonders for taste. This top quality stainless steel protects against any flavour transfer which means that after a quick rinse you can use the same flask for multiple different drinks throughout the day and it won't taste like stale coffee. It is super easy to clean (yes, even if you accidentallyleave it half-full of coffee in your car over a hot weekend) and is also BPA-Free and Phthalate-Free. The slip-free proprietary powder coating makes your bottle much easier to carry and keeps your bottle secure in your hand. Plus, this little coffee flask will fit under most coffee brewing systems in coffee shops eliminating the need for a disposable cup.