Thermal wear is one of those clothing accessories that serve as a necessity during the winter season, especially in cold countries. This form of clothing has been popular over a long time due to the comfort these offer, that generally negate the need for additional clothes. Previously, these clothes were used as inner only. However, recently all forms of thermal wear have been upgraded with further design options thus enabling them to be used as normal clothing and standalone winter wear. The popularity of thermal wear is not influenced by factors like aesthetic or comfort value, but by their usefulness and the overall advantage they offer over normal clothing.
Some features of a thermal wear 
The functioning of a thermal wear works on the principle of insulation. The material used in these clothes basically adds a layer of insulation between the body and the garment. The material absorbs minimal amount of moisture from the body, allows quick drying and regulates air flow in the insulating layer that is formed. The material is closely knitted and tightly weaved so that the thermal wear retains the warmth produced by the body. The extra layer of polyester on the inner surface allows better moisture retention, and helps to keep the skin dry. Cotton does not offer the insulating properties when it becomes wet. However, this is not a case with wool as it allows insulation even when it is wet. Also, wool is a naturally occurring fire retardant, and is hence advantageous over cotton. How are they used? 
Although predominantly used in cold countries, thermal wear are the most common clothing in all places throughout the world. Their transition from being inner garments to serving as upper wear has gained these pieces of clothing far greater popularity over the years. Besides being available for all body components separately, they are also available in the form a long unified suit. In most cases, thermal wear can be used without any supplementary clothing.
Final words
The importance and usefulness of thermal wear is unparalleled due to the comfort and warmth they offer during the cold. Unlike other winter clothing, these can be worn over the skin, and the tight weaving provides body comfort like any other normal clothing. A thermal wear is one of the essential pieces of clothing that offer aesthetic usefulness, warmth and comfort at the same time.

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