The LAPASA Women's Lightweight Thermal Underwear Bottoms are a top-rated option for women's synthetic base layer bottoms on Amazon. These bottoms are made with a blend of polyester and spandex, offering a lightweight and stretchy fit. The lightweight fabric provides warmth without adding bulk, making them suitable for layering under clothing. These bottoms have a brushed interior for added comfort and insulation. The moisture-wicking fabric helps to keep you dry and comfortable during intense activities. These baselayer bottoms have a wide waistband and a form-fitting silhouette for a comfortable and flattering fit. They are available in different sizes and colors to suit individual preferences.