Polyester. Quick Dry, Lightweight, Breathable, Comfortable The fast drying fabric keeps you cool and dry during various sports activities Mens Athletic Short sleeve shirt made with 100% polyester fabric features lightweight, quick dry and breathable, also durable for your long time wear Moisture Wicking, Crew Neck, Short Sleeve, Tag Free, Stretch, Skin-Friendly Perfect for running, workout, training, jogging, fitness, exercise, bodybuilding, athletic wear and everyday activities