Vital Salveo germanium Men Hollow Quick-Drying Warm High-Collar Shirt Far infrared improves circulation and metabolism. Far infrared - Prevent soreness and discomfort, eliminate fatigue, increase body oxygen levels, restore energy by penetrating subcutaneous tissues. Negative ions give you full of vitality. Negative ions - heal body, relieve chronic fatigue and restore energy by improving blood flow and increasing oxygen-carrying capacity. Germanium fiber release far infrared and negative ions. The design combined with the hollow fiber section and Y-section to reach 20-25% light effect. It has soft feeling and fluffy, wicking and quick-drying good effect. Also having excellent insulation effect. It is suitable for sport, outdoor clothing and other application.