super unique and technical fabric, I am so intrigued with this piece. it's designed so carefully and the detail is gorgeous and so functional. it's ultra light weight like crazy, but fits in all the right ways and feels cozy. the mesh underarms feel so refreshing. this would definitely be great for distance runners, night joggers, long distance endurance hikers and marathoners. hoping this finds a great home, sadly just too small for me. might trade for a size large!! excellent condition, I didn't see any flaws. photos are taken with and without flash so you can see the reflective strips