This is the Lavacore Polytherm Socks with Tough Sole for Scuba Diving Snorkeling etc. Features: Wind-proof middle layer provides anti-wind chill properties and ensures warmth in cold conditions Water resistant outer layer facilitates fast water run-off and quick drying Light weight and 4-way stretch makes Lavacore incredibly comfortable to wear Breathable middle layer allows moisture to be drawn away from the body on the surface Lavacore is neutrally buoyant All seams are overlapped during flatlock sewing to decrease water flow Full gusset incorporated into the underarm to offer exceptional arm movement and stretch Anti-bacterial inner fleece minimizes odor and eliminates bacteria growth Extended material on back to keep vests and shirts from riding up SPF 30+ protection Tough Sole for added protection The perfect thermal accessory used stand alone inside a snorkeling fin, or underneath a specific exposure boot for added warmth, comfort and breathability.