The outer casing of the thermal flask can be made from materials such as woven bamboo, plastic, sheet metal, aluminum, or stainless steel. Inside, a rubber gasket at the neck and a bowl-shaped rubber base at the bottom secure the glass liner, preventing it from colliding with the outer casing. The area around the flask's neck is the most vulnerable point for heat loss or gain, as heat transfer occurs most readily there.
Usage Precautions
1. When not in use for an extended period, ensure the inner liner is kept completely dry.
2. To prevent odors or stains, wash the flask thoroughly with a neutral detergent after use and allow it to dry completely.
When cleaning, use a soft brush, hot water, and detergent to clean the interior, then rinse with hot water. For stubborn stains, fill the flask with hot water, add a spoonful of sodium carbonate (soda), let it sit for a while, and then rinse thoroughly.
3. For stubborn tea stains or grime accumulated from prolonged use, soak the flask in a mixture of white vinegar and warm water for half an hour, then wash thoroughly.
4. Avoid dropping, knocking, or subjecting the flask to strong impacts, as this may deform the product and impair its functionality.
