Heat Retention - This women's thermal base layer offers excellent warmth and comfort. We've enhanced the comfort and warmth of the tops and bottoms by reducing unnecessary seams, providing a better wearing experience. Comfortable Fabric - Made from 73% Bamboo Rayon, 23% Nylon, and 4% Spandex, this base layer set for women features excellent thermal performance, effectively blocking cold air and ensuring warmth in cold weather. Fit & Stretchy - The fabric of this women's thermal underwear base layer is stretchy, adapting to various body shapes and providing freedom of movement. If you prefer a slightly looser fit, please choose a size up Moisture Wicking - These women's thermal base layer sets are equipped with breathable and quick-dry fabric, which wicks away sweat with excellent breathability to keep you dry and comfortable without feeling stuffy. Versatile Usage - This women's thermal set is wonderful for lounging at home or for outdoor activities like skiing, skating, running, cycling in winter. It ensures excellent warmth and comfort in various activities.