The 32 DEGREES Women's Heat Base Layer Legging is a top-rated flannel base layer bottom for women on Amazon. These leggings are made from a blend of polyester and spandex, which provides excellent warmth and flexibility. The flannel lining adds extra insulation and softness, making them perfect for cold weather activities. The wide waistband and four-way stretch fabric ensure a comfortable and secure fit. With its stylish design and affordable price, these leggings are a popular choice among women.