Stainless steel vacuum cup construction
Source：https://baike.so.com/doc/1634631-1728010.html Release time：2019/4/11 9:37:00
There are many layers inside the thermos cup, and its interlayer is usually vacuum, to prevent the conduction of heat, and then the electrolysis treatment, which can prevent heat radiation. Some have a cork on the lid to prevent heat transfer.