The raw material of heating underwear is a special fiber material, which is expensive. Generally speaking, thermal underwear is a combination of a small amount of thermal fibers and other fibers. Therefore, even if it is really hot underwear, the temperature will not rise very high, generally 2℃ to 4℃ can be actively heated.

Relevant experts remind the public to pay attention to anti-counterfeiting when buying thermal underwear. At the same time, we should also realize that even if it is really hot underwear, the temperature rise is limited and it cannot be used to replace cotton-padded clothes.

Extended data;

The principle of heating warm clothes;

1. The raw material of heating underwear is a special fiber material introduced from Japan around 2000, which actively heats up by absorbing moisture emitted by human body. This fiber material was first used for mountaineers, and later extended to the general consumption field, mainly used for making underwear.

2. The materials used in the heating underwear produced by domestic manufacturers are all imported from Japan. Due to the high price of this fiber material, ordinary heating underwear is made of a small amount of heating fiber mixed with other fibers.

Yang Shibin, chairman of China Knitting Industry Association, added that, therefore, the real temperature rise of heating underwear can't reach such a high level. Generally, it can actively raise the temperature by 2℃ to 4℃.

Reference source; Baidu encyclopedia-fever underwear