The 21 oz. Standard Mouth Bottle equipped with Hydro Flask's insulated Sport Cap is the perfect go-anywhere companion on your busiest days. 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. Versatile, middle-of-the-road size, equipped with the insulated Sport Cap. Temp Shield™ 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 the Standard Mouth Flex Cap. Lifetime Warranty. Holds 621 m L/21 oz. 1.91 in. mouth diameter. Measures 2.87 in. wide by 10.4 in. tall. Weighs 11.3 oz. Imported. Hydro Flask 21 Oz. Standard Mouth Water Bottle With Sport Cap.