Men's base layer :

The mission of a first layer is above all to manage the humidity produced by the body. This first layer is used to evacuate sweat and depending on the type of sport activity, it must also keep you warm or cool.

To be effective, it must be tight fitting without being too tight in order to transport moisture to the outside while keeping you warm. A first layer should have a good odor protection, it should also keep you warm and dry.