Vacuum Insulated - triple-layered construction, designed to keep beverages cold for 24 hours or hot for 12..TRIPLE-LAYERED INSULATION: S’well Traveler Azurite 20oz stainless steel travel / coffee mugs feature triple-layered, vacuum-insulated construction, designed to keep beverages cold for up to 28 hours or hot for up to 15 with our exclusive Therma-S’well Technology. Each Traveler Mug features unique colors, prints, patterns and textures, all while delivering superior functionality. Hand-wash only..THE PERFECT FIT: Our metal beverage containers are designed with an opening wide enough for most ice cubes so you can easily refill and reuse it over and over. Whether you're hitting the road, or headed to a meeting, or the gym, you’ll find S’well fits just right in most standard-size cup holders..DON’T SWEAT IT: Toss your bottle in your bag without worrying about spills, drips, or condensation. S'well beverage containers are insulated with a copper wall layer to make your mug sweat-free and feature a leak-free top for added spill protection..WORRY-FREE HYDRATION: Your search for safety is over. All S’well containers are BPA-free and composed of 18/8 premium food-grade stainless steel. We are compliant with California Prop 65 regulations and our products are certified to meet all regulatory requirements by an independent and accredited testing facility.