Come and see our amazing products. Double-wall vacuum insulation. Great quality and design keep your liquids cold or hot for up to 12 hours. Samples available upon request. Smooth sleek swell design is great for all types of promotional outings. Great for company gifts and for self-promo items. This 500ml Thermo Flask is made of stainless steel which can maximum guarantee the heat preservation time was more than twice the normal temperature. Pls confirm further with us if any query about packing info, inventory status and time schedule.