Sunland Men's Compression Base Layer Long Sleeve T Shirts for Running Sporting Top XL. Polyester 92%, Spandex 8%. Soft, breathable and moisture-wicking fabrics keep you dry and comfortable. Stretchy and durable material grabs your muscles tightly and improves your performance. Great for skiing, snowboarding, training, competing, and all weather sports and activities. Super scalability, If you are a big muscle, Please order 1 Size Up than you normally wear on USA Size.