Hydro Flask 21 oz Double Wall Vacuum Insulated Stainless Steel Sports Water Bottle, Standard Mouth with BPA Free Sport Cap DESIGN IN MIND: Standard Mouth is ideal for sipping, while still accommodating ice cubes. Also, safety is top-of-mind, as the bottles are made out of non-toxic BPA-free plastics & 18/8 food-grade stainless steel. SLIP-FREE GRIP: Unlike other leading water bottles, Hydro Flask has a powder coat, which gives you a solid grip. The Powder Coat works with the premium TempShield insulation, which prevents condensation from forming on the outside of the bottle, to give you exactly what you want in an everyday refreshment delivery system. JUST THE RIGHT SIZE: Meets your everyday hydration needs in one container, all while keeping it piping hot or ice cold and fitting comfortably and conveniently in your hand or your vehicles' cup holders and bicycle bottle racks. INSULATION INNOVATION: The double-walled, vacuum insulated TempShield Insulation, the same technology used in all Hydro Flask products, will ensure that your beverage of choice maintains its temperature for many hours to come. Hot drinks up to 6 hours, and cold drinks up to 24 hours. ONE-HANDED REFRESHMENT: From mountain trails to morning yoga class, the Standard Mouth Insulated Sport Cap lets you hydrate one-handed and on the fly. Its the first insulated sport cap specifically designed to keep water in your Hydro Flask bottle ice cold, sip after sip.