If you're serious about staying hydrated, the Iron Flask® 64-ounce Narrow Mouth Bottle with Spout Lid has your back. Made from high-grade stainless steel, this double-walled, vacuum-insulated bottle keeps your drink cool as a cucumber for 24 hours or piping hot for 12 hours with no bottle sweat. The leakproof spout lid and narrow mouth make it easy to chug and be free of worries when it's stashed away in your bag. And we included a flip lid and a screw-on lid, so you can switch them around depending on the day's activity.