The Smartwool Women's Merino 250 Base Layer Bottom is a top-selling flannel base layer bottom for women on Amazon. These bottoms are made from high-quality merino wool, which provides excellent warmth and moisture-wicking properties. The flannel lining adds extra insulation and softness, making them perfect for cold weather activities. The wide waistband and flatlock seams ensure a comfortable and chafe-free fit. With its superior quality and performance, these bottoms are a favorite among outdoor enthusiasts.