To make your choice easier, Patagonia uses the so-called temperature index. It can help you find your way around jackets immediately. On a scale from 1 to 10 the higher the number, the warmer the jacket. The temperature rating is determined in the test laboratory under constant conditions, so it is possible to compare the jackets. Of course, the feeling of warmth is relative and depends not only on weather conditions but also on your subjective resistance to cold and the layers you wear. Nevertheless, the defined temperature index is a great way to categorize jackets, which gives you an idea of their function and leads you to the best choice.