This listing is for a men's Lululemon Metal Vent Tech exercise t-shirt. Size medium and made of 56% nylon, 40% polyester and 4% elastane. Used and in great condition. If you have any questions please do not hesitate to ask and thanks for looking :) Measurements: Across Chest (pit to pit): 20.5" Length (collar to hem): 27.5" Sleeve Length (armpit to end of sleeve): 4"