Vapourlite fabric Lightweight and breathable with a quality wicking treatment Reflective graphics Grid mesh panelling for added ventilation Flat-locked seams Get in to the race with the Momentum Short Sleeve T-Shirt from Ronhill. The lightweight, breathable vVapourlite fabric that wicks away sweat to leave you dry, comfortable and focused on your run. With flat-locked seams, grid mesh panelling for added ventilation and reflective graphics that are ideal for low-light runs.