Is the cotton inside the jacket cotton?

Yes. Cotton is a common natural fiber with good warmth and breathability, and is commonly used to make a variety of textiles, including cotton jackets. Cotton jacket is a kind of top worn in winter, usually made of cotton filling, which has a strong warming effect. In addition to cotton, the filling of a quilted jacket can also include materials such as down and wool, which also have good warming properties. When making a cotton jacket, a layer of fabric is usually added to the outer layer of cotton or filler as a fabric to provide better warmth and comfort.