NIKE Training Shirt Aerolayer Repel Strike Drill Shirt Seaweed/Volt Mens Size Medium Body: 100% Polyester Aero Repel Strike Drill is constructed with the Aerolayer technology with the purpose of keeping you warm, dry and comfortable by combining a interlining of thermal material, a water repellent upper and a breathable lining The stretch of the shirt follows the body's movement , while the raglan sleeves secures you the best possible movement. A zip by the left side seams makes it easier to get in and out of the shirt. It also has thumb holes which gives a better fit.