Here's a warm idea. Check your head into the 2mm Marathon Sessions Surf Cap and say goodbye to brain freeze for good. Nothing stops a great session faster than too-cold water. But our StretchFlight neoprene promises continuous warmth and plenty of flex comfort. Plus, glued and blind stitched seams block out water like a beast. And because sustainability is just as important as high quality, this surf cap is officially Bluesign certified.