Arc'teryx Rho AR zip-neck base layer in black features a moisture-wicking Polartec Power Stretch fabric that provides thermal regulation and comfort during high-output activities. This versatile piece includes a zippered chest pocket with a laminated finish and a tall collar for added warmth. The garment is detailed with a 'rootly' corporate logo on the right chest, complementing the classic Arc'teryx bird logo on the pocket. Designed with a trim fit and flatlock seam construction, it minimizes bulk and prevents chafing under layers.