Selected 304 stainless steel material, real material, protects your drinking water safety. Double-layer vacuum insulation, no condensation on the outside, no sweat on your hands or in your bag. Keeps drinks hot or cold for hours. bottle mouth fits most ice cubes. bottle mouth fits most cup holders. BPA-free and reusable. FDA and Prop 65 compliant. The lid has a built-in 360?? silicone seal, so you can shake and flip it over without worrying about leaks, and fill your bag with your favorite drink.