Fly Racing Dirt Lightweight Base Layer Top The Fly Racing Lightweight Base Layer Top is engineered with hollow-core fibers that excel in moving moisture away from the skin, allowing it to dry rapidly on the surface. Designed with comfort in mind, it employs flat-lock seams and stretch fabric, ensuring a full range of motion without sacrificing warmth. This top not only maintains comfort throughout the day but also offers UPF 40+ sun protection. Integrated Polygiene odor control technology keeps unpleasant smells at bay, making it a reliable companion for extended outings in the sun. Features: Fast wicking hollow-core fibers transport moisture to the outer surface to dry quickly Flat-lock stitch seam construction Multi-direction stretch fabric allows for un-restricted range of motion Open fabric structure offers lightweight warmth and all day comfort UPF 40+ sun protection Polygiene odor control technology Ergonomic panels are form fitting (non-compression)