Double-walled and vacuum-sealed stainless steel - keeps contents hot or cold for hoursPerfect for hot or cold beverages - does not sweat (for cold contents) or burn your hand (for hot contents) Contoured design - makes the bottle easy to hold and visually distinctive from the many, many straight-walled bottles Removable mesh filter - keeps ice from blocking the drinking spout and allows users to conveniently brew tea on the go Unsurpassed testing for material safety - our products undergo rigorous chemical and biologic testing to ensure they do not contain toxic chemicals