The Hydro Flask Standard Mouth 621 ml stainless steel water bottle with Flex Straw cap is designed for convenient hydration on the go. The leakproof, closeable straw cap allows easy one-handed drinking, making it ideal for workouts, travel and everyday use. Featuring TempShield® double-wall vacuum insulation, it keeps drinks cold for up to 24 hours. Its slim design fits most cup holders for added convenience, while the durable stainless steel construction is built for long-lasting performance. Dishwasher safe for easy cleaning. The Flex Straw cap is not intended for hot liquids. Not suitable for use in a microwave, freezer or on a stove.