Our mid-weight high-performance thermal long underwear is uniquely engineered to keep you warm and dry during outdoor activities that require physical exertion, such as skiing, hiking, snowshoeing and running. Because the extraordinary wicking ability of this Polyester fabric and the ribbed construction draws moisture away from your skin, you stay warmer and dryer than with cotton thermals. Compared to our heavy duty ECWCS Polyester thermals, these are surprisingly thin and lightweight, making them perfect for layering under casual or business clothes when you require extra warmth. The navy blue color also makes them ideal for use with law enforcement or security uniforms.This listing is for one brand new thermal top in a sealed package.