TCA Men's & Boy's SuperThermal Compression Shirt Base Layer Thermal Long Sleeve - Mock Neck TCA compression fit works on key muscles to improve power and endurance Flat lock seams eliminate skin irritation Soft brushed inner fabric locks in heat for exceptional warmth Moisture wicking fabric is QuickDry and absorbs sweat from the skin keeping you dry and comfortable 3DAirMesh panels provide strategic ventilation in high heat zones