The Womens ellesse Tennis Base Layer LS shirt will preserve heat to keep you warm all year round while also ensuring that sweat is wicked away quickly from the skin for comfort. The ellesse base layer features layering technology with SOCOOL! patended fabric. The layering technology consists of a top & bottom base layer. The top layer works by cooling the arms through shielding skin from the heat of the sun. The bottom layer helps reduce moisture therefore discomfort around the upper leg & lower back. The ultra light 4-way stretch fabric enables the player to move easily & comfortably.