The Carhartt Women's Base Force Heavyweight Bottom is a top-rated flannel base layer bottom for women on Amazon. These bottoms are made from a heavyweight and durable fabric that provides excellent warmth and insulation. The flannel lining adds extra comfort and softness, making them perfect for all-day wear. With a relaxed fit and stretchy waistband, these bottoms offer a comfortable and flexible fit. Whether you're working outdoors or just running errands, these bottoms are a reliable and practical choice.