Before use, in order to have a good thermal insulation effect, it is best to preheat or cool with boiling water or cold water for about 10 minutes.
It is not advisable to add water to the thermos cup for the first time, so as to avoid boiling water and scalding when the cup lid is tightened. The first time you use a thermos cup, its insulation performance is definitely good, so be careful when drinking hot drinks in a thermos cup. Don't judge mistakes and burn.
After the cup is used, it must be cleaned in time. It is best to use a soft cloth and a food detergent diluted with warm water. The inside of the stainless steel vacuum flask may sometimes produce some red rust spots due to the presence of iron and other substances in the container. At this time, it can be easily removed by immersing it in warm water and diluted vinegar for a period of time and then cleaning it.