Outer Shell:
* Stainless Steel: Most common material for the outer shell. It's durable, rust-resistant, and can withstand high temperatures.
Inner Vessel:
* Stainless Steel: Also used for the inner vessel. A double-walled construction is used, with a vacuum between the walls.
Other Components:
* Vacuum: The vacuum between the walls is essential for insulation. It prevents heat transfer through conduction and convection.
* Lid: Typically made of stainless steel or plastic. It includes a seal to prevent heat loss.
* Insulation: Some models may use additional insulation, such as polyurethane foam or glass wool, to further enhance the thermal performance.
Note: While stainless steel is the most common material for thermal flasks, some models may use other materials for specific components. For example, some lids are made from plastic, and certain parts of the flask might be made from rubber or silicone.
