This adidas cap is made of breathable mesh material. I bought it a few years ago for running and wore it once, but the size didn't fit, so I've kept it in storage since then. It's very light, so I think it would be great for use at the gym or for running. - Brand: adidas - Color: White Beige - Style: Cap - Features: Mesh material, adjustable back strap Stored by a private individual.