Running during the fall can be both invigorating and challenging the cool conditions can affect your breathing rhythm which, as most runners know can consequently throw off your entire training. However most importantly, these colder temperatures often mean less daylight hours and decreased amounts of visibility so don't get caught in the dark without the Nike Men's Aeroloft Flash Vest. This high visibility vest caters to both maintaining core warmth and keeps you visible to drivers, fellow pedestrians, and bikers. Crafted with 800 fill goose down, the Aeroloft Flash keeps your core toasty warm with its water resistant, ripstop exterior, ultimately ensuring maximum protection should those dark, overhead clouds begin to release a little rain. The laser perforated fabric encourages optimal body temperature regulation without the fuss and fumble of zippered ventilation while the Dri FIT mesh shoulder panels assist you in staying cool and dry. Additionally, the Aeroloft Flash packs down securely into the back pocket and comes complete with a hand strap so you can run with ease and assurance knowing you'll be well protected.