How to see whether a down jacket protects warm or not?
Puffy down jackets store air across each other for best insulation by trapping heat, so try to buy puffy ones. When choosing a down jacket, press the garment by hand and release it quickly to return to its original shape.
Down is a mixture of "feather" and "down", in which the fluffy ball structure can fix a lot of still air, so the higher the down content of the down jacket will be better insulation effect, as the general down content of more than 80%, it is a good down jacket.
Down jackets on the market are common with duck down, goose down, and wool, cotton, silk, etc., goose down is the best warmth protection, followed by duck down, so when buying down jackets, try to choose goose down or duck down.