Hydro Flask 21 oz Standard Mouth Water Bottle Mint Turquoise Insulated Stainless Hydro Flask 21 oz Standard Mouth water bottle in a vibrant turquoise Mint color. This insulated stainless steel bottle features the signature TempShield double-wall vacuum insulation to keep beverages cold or hot for hours. It comes equipped with a black insulated Flex Cap for easy carrying and a leak-proof seal. The durable powder-coated finish provides a slip-free grip, while the slim profile fits easily into most cup holders and backpack side pockets. Measurements: • Capacity: 21oz (621mL)