Iron Flask Classic Tumbler, Rose Gold, 32oz/950mlIron Flask Classic Tumbler, Rose Gold, 32oz 950ml. Our functional and stylish 32 oz Classic Tumbler is made with non toxic 18 8 grade stainless steel and double walled vacuum insulation, so you know your favorite drink will stay cold for 16 hours and hot for 4 hours and will never sweat, have a metallic taste or create a funky smell. Every tumbler cup is finished with a powder coating, so you know it will look out of the box long after the drops,