The Insulated Flask 500ml is a thermal flask, designed to keep drinks hot or cold. This column flask is made of double-walled stainless steel, durable and odorless, with an insulated air chamber. It keeps drinks cold for 12 hours or hot for 6-8 hours. Completed with a food-grade polycarbonate screw cap, this flask allows for a limited flow for drinking and a secure seal for transport.