While not strictly spandex base layer bottoms, the Columbia Women's Glacial IV Print 1/2 Zip Fleece Pullover is a popular choice for layering during colder weather. This pullover is made with a soft and cozy fleece fabric that provides warmth and comfort. The half-zip design allows for easy ventilation and temperature control. It features a stylish print and is available in various colors. Whether you're hiking, skiing, or simply running errands, this fleece pullover will keep you warm and stylish.