Borrowing from our premium headwear development, and a continuation from our spring summer FSTTshirt, the FSTLongsleeve adopts a 94% recycled COOLmatic | PLUS micro mesh for lightweight, quick dry as well as cooling and anti-odour technologies. Reflective details keep you lit from dusk to dawn. A thumbhole on the sleeve keeps hand warmth a notch higher on those crisp autumn runs, and in place if you decide to layer up for it. Engineered, always on side vents, insure air circulation for an extra layer over the top. Flatlock stitching and critical welding alleviate much maligned chafing and elevate this essential long sleeve to premium status.