Fourth Element Xerotherm Women's LS TopFourth Element Xerotherm Women's LS Top The Fourth Element Xerotherm Women's LS Top is the epitome of baselayer excellence, designed to provide unparalleled comfort and performance under a drysuit. Crafted using Polartec Powerstretch fabric, originally developed for NASA, the Xerotherm traps a layer of air next to the skin, offering superior insulation and comfort, even in the harshest conditions. Fourth Element Xerotherm Women's LS Top Key Features: