Double-walled, to enjoy iced water or hot drinks for many, many hours! • With a sports straw cap • Suitable for bicycle cases • Made of 304 stainless steel (18/8 stainless steel) • With FDA & SGS quality certificates • Free of aluminum and toxic substances (BPA free) • It doesn't break • 100% recyclable • Double-walled to maintain the temperature for longer hours The most important reason to say "yes" to stainless steel water bottles is their healthy material & their great durability over time. Since they do not break if dropped, they can be used for a much longer period of time than regular water bottles. Stainless steel is the healthiest & safest material, as it does not contain Bisphenol & Carcinogens, as is the case with some poor quality plastic or aluminum containers. In addition, stainless steel does not accumulate bacteria, even if scratched. Let's not forget that it is the first choice of material for the manufacture of hospital accessories & kitchen items. - Not suitable for carbonated drinks.