Plenty of folks put lots of emphasis on outerwear — after all, it's what everyone sees — but not as many people focus on what's underneath. The next-to-skin layers are arguably more important, which is why Pearl Izumi made the Transfer Wool Long-Sleeve Women's Baselyer from a moisture-wicking, breathable, and antimicrobial blend of merino wool and polyester. It will help you stay warm when it's cold and fresh as morning dew all year round. Plus, it has a cycling-specific cut, with a dropped back hem for full coverage, rotated sleeves for comfort, and thumbholes to help your sleeves stay in place.