This is the performance short sleeve shirt made from bamboo fibers, so it won’t retain odors like technical apparel knit from man-made materials. Unlike scratchy, chemically-treated fabrics that smell unpleasant when you sweat, soft bamboo is naturally anti-bacterial and odor-resistant, and remains so no matter how often it is washed. The certified organic bamboo undergoes a proprietary finishing process and is blended with cotton and elastane to yield a fabric that feels smooth against the skin, is lightweight and breathable, allows freedom of movement, and wicks moisture away to help you stay dry and comfortable. The shirt is knit using state-of-the-art knitting machines to achieve the smoothest fabric possible. UPF 50+ protection blocks 98% of the sun’s harmful rays. 55% organic cotton/40% viscose from bamboo/5% elastane. Machine wash. Navy. Men’s sizes S-XXL. (1/2 lb.)