4 hours after it reaches room temperature.
Long Johns for pants thermos but I dont know what the shirts are called.
you fill the thermos bottle with liquid in gas occlusion's
keep it in a hot place
A high-quality thermos can keep water cold for 24-36 hours, depending on the initial temperature of the water and the surrounding conditions. It is important to pre-chill the thermos before using it for maximum efficiency.
If you look inside of a thermos you will see metal. This absorbs the heat or the cold and keeps it that way for as long as the contents are in the thermos.
To clean and maintain a milk thermos for long-lasting use, rinse it with warm soapy water after each use, use a bottle brush to scrub the interior, and let it air dry completely. Avoid using harsh chemicals or abrasive cleaners, and store the thermos with the lid off to prevent odors.
To keep a thermos hot, pre-heat the thermos with boiling water before adding the hot liquid. For cold beverages, pre-chill the thermos with cold water or ice cubes. Keep the lid tightly closed to maintain the temperature inside.
thermos cup
a long time probably 9-10 hours at the most if not longer
A thermos bottle (Actually a thermos container, which has a wider lid) will work.
Stainless steel is a popular material for thermos flasks because it is durable, has good insulating properties, and is easy to clean. Vacuum-insulated stainless steel thermos flasks can keep liquids hot or cold for long periods of time.
I wouldn't see any reason why you couldn't keep a thermos in the refrigerator. Pre-chilling containers for cold beverages is a good idea anyway. ====== ======