They're pretty much the perfect pair—the Hydro Flask 21 oz Standard Mouth Bottle and insulated Sport Cap. Together, they're your go-anywhere hydration companion. It stashes easily in a small shoulder bag, your pack’s side pocket, or your car cup holder, and holds enough to keep you going for hours without weighing you down.

Features and Benefits

• Versatile, middle-of-the-road size, equipped with an insulated Sport Cap
• TempShield™ insulation eliminates condensation and keeps beverages cold up to 24 hours and hot up to 12 hours
• Durable 18/8 Pro-Grade Stainless Steel construction
• BPA-Free and Phthalate-Free
• Compatible with all standard mouth caps
• Sport Cap is not intended for use with hot liquids and is not leakproof