The Women Comp X 5.5/4.5mm falls in the top tier of the performance and warmth categories. Great suits for our beach break here on Vancouver Island. It offers a light weight Channel Flex exterior which maximizes stretch, combined with the exclusive Thermo Dry Celliant (TDC) infrared interior that penetrates deeper into the body's core for added warmth. This suit also offers completely sealed seams, and 1 piece front and back panel design.